Evidence map

All 716 uses on this site’s 123 compound pages, sorted by body system and by where the evidence comes from: approved labels, studies in people, animals only, or claims with no data.

Weight, fat and appetite 8613 on labels, 50 tested in people, 12 in animals only, 11 claims only Blood sugar and diabetes 4512 on labels, 27 tested in people, 6 in animals only Heart and blood vessels 336 on labels, 17 tested in people, 7 in animals only, 3 claims only Liver 213 on labels, 14 tested in people, 2 in animals only, 2 claims only Muscles, bones and joints 909 on labels, 35 tested in people, 23 in animals only, 23 claims only Skin, hair and wounds 736 on labels, 30 tested in people, 20 in animals only, 17 claims only Brain, mood and nerves 8912 on labels, 46 tested in people, 23 in animals only, 8 claims only Sleep 191 on a label, 10 tested in people, 8 claims only Hormones, sex and reproduction 7024 on labels, 29 tested in people, 2 in animals only, 15 claims only Stomach and gut 3910 on labels, 15 tested in people, 8 in animals only, 6 claims only Immune system and infections 308 on labels, 9 tested in people, 6 in animals only, 7 claims only Aging and longevity 359 tested in people, 18 in animals only, 8 claims only Cancer and cancer care 369 on labels, 12 tested in people, 15 in animals only Alcohol, smoking and drugs 121 on a label, 8 tested in people, 1 in animals only, 2 claims only Eyes 92 on labels, 6 tested in people, 1 in animals only Kidneys and bladder 183 on labels, 6 tested in people, 6 in animals only, 3 claims only Lungs and breathing 113 tested in people, 5 in animals only, 3 claims only

On a labelTested in peopleAnimals onlyUser or seller claimsNo study

Each use is counted once, under the body system it mainly concerns. Uses in children and veterinary uses are left out. The answers are the same ones shown on each compound’s page, with their sources there. By condition: conditions A to Z.

Animal results

155 of these uses rest only on studies in animals or cells, and none of them has been shown to work in people. Animal results are a reason to test something, not evidence that it works: in a 2024 review of 367 treatments first tested in animals, 50% went on to any study in people, 40% to a randomized trial and 5% to approval, typically about 10 years later.

Weight, fat and appetite 86

On a label 13

Approved uses, from a product label somewhere in the world.

SemaglutideApproved drug: LabelWeight loss in obesity or overweight. Wegovy is approved for adults and for teens 12 and older with obesity. In STEP 1, adults lost 14.9% of body weight vs 2.4% on placebo at 68 weeks, counting everyone randomized.
TirzepatideApproved drug: LabelWeight loss in obesity or overweight. Zepbound is approved for adults with obesity, or overweight with a related condition. In SURMOUNT-1, adults lost 15.0–20.9% of body weight vs 3.1% on placebo at 72 weeks, counting everyone randomized.
L-CarnitineApproved drug: LabelInherited carnitine deficiency. Approved: Carnitor tablets and oral solution treat primary carnitine deficiency; these and the IV injection treat deficiency caused by inherited metabolic disorders, in adults and children.
LiraglutideApproved drug: LabelWeight loss in obesity or overweight. Saxenda and generic pens are approved for adults and for teens 12 and older weighing over 60 kg. Over 56 weeks, adults lost 7.4% of body weight vs 3.0% on placebo, counting everyone randomized.
OrforglipronApproved drug: LabelWeight loss in obesity or overweight. Foundayo tablets are approved for adults. In ATTAIN-1, adults without diabetes lost 11.1% of body weight on 17.2 mg vs 2.1% on placebo at 72 weeks, counting everyone randomized.
OrforglipronApproved drug: LabelWeight loss with type 2 diabetes. Covered by the same approval. In ATTAIN-2, adults with type 2 diabetes lost 9.6% on 17.2 mg vs 2.5% on placebo at 72 weeks, counting everyone randomized; HbA1c fell 1.7 points.
EcnoglutideApproved drug: LabelWeight loss in obesity or overweight. Approved in China since March 2026 for adults. In SLIMMER (664 Chinese adults), weight fell 9.1–13.2% on 1.2–2.4 mg vs a 0.1% gain on placebo at 40 weeks, counting everyone who got a dose.
SetmelanotideApproved drug: LabelAcquired hypothalamic obesity. Approved from age 4 for obesity after brain tumors, surgery or injury affecting the hypothalamus. In TRANSCEND, BMI fell 15.8% vs a 2.6% rise on placebo over 52 weeks.
SetmelanotideApproved drug: LabelObesity in Bardet-Biedl syndrome. Approved from age 2 for this rare genetic syndrome. BMI fell 4.6% vs 0.1% on placebo over 14 weeks, and 7.9% on average after a year of treatment.
SetmelanotideApproved drug: LabelObesity from POMC, PCSK1 or LEPR deficiency. Approved from age 2 when gene testing confirms it. After a year, 80% with POMC or PCSK1 and 46% with LEPR deficiency lost at least 10% of body weight.
TesamorelinApproved drug: LabelBelly fat in HIV lipodystrophy. Approved for adults with HIV and excess belly fat. In two 26-week trials, deep belly (visceral) fat fell 18% and 14%, vs a 2% rise and a 2% drop on placebo; it returned after stopping.
TesamorelinApproved drug: LabelWeight loss. Not a weight-loss drug: the label calls it weight neutral and says it isn’t indicated for weight loss. In the main trials, body weight barely changed even as belly fat fell.
hCGApproved drug: LabelWeight loss (the “hCG diet”). Not shown: the urine-derived hCG labels state it hasn’t been shown to aid weight loss beyond calorie restriction, improve fat distribution or curb hunger. A review of 24 trials agreed.

Tested in people 50

Studied in people, whatever the result: some worked, many didn’t or are unproven.

RetatrutideHuman studies: TrialWeight loss in obesity. Positive: in TRIUMPH-1 (2,339 adults without diabetes), weight fell 17.6–25.0% vs 3.9% on placebo at 80 weeks, counting everyone randomized. Not approved anywhere.
RetatrutideHuman studies: TrialWeight loss with type 2 diabetes. Positive: in TRIUMPH-2 (1,152 adults with obesity and type 2 diabetes), weight fell 11.9–18.8% vs 5.1% on placebo at 80 weeks, counting everyone randomized.
CagrilintideHuman studies: TrialWeight loss (on its own). Promising, not approved: in a 26-week trial of 706 adults, weekly doses cut weight 6.0–10.8% vs 3.0% on placebo, if everyone had stayed on treatment; counting everyone randomized gave similar results.
CagrilintideHuman studies: TrialWeight loss with semaglutide (CagriSema). Positive, not approved anywhere: in REDEFINE 1 (3,417 adults), the weekly pair cut weight 20.4% vs 3.0% on placebo at 68 weeks, counting everyone randomized.
CagrilintideHuman studies: TrialWeight loss with type 2 diabetes. Positive, not approved: in REDEFINE 2 (1,206 adults with type 2 diabetes), CagriSema cut weight 13.7% vs 3.4% on placebo at 68 weeks, counting everyone randomized.
AOD9604Human studies: TrialWeight loss in obesity. Not shown: in the 502-person OPTIONS trial, weight loss with daily tablets didn’t differ significantly from placebo at 12 or 24 weeks; development for obesity stopped in 2007.
L-CarnitineApproved drug: TrialWeight and fat loss. Modest: in a meta-analysis of 37 supplement trials (2,292 people), weight fell 1.21 kg and fat mass 2.08 kg more than control. Injections for fat loss haven’t been tested.
ExenatideApproved drug: TrialWeight loss. Modest, never approved for it: in a 24-week trial of 152 adults with obesity but no diabetes, exenatide plus lifestyle advice cut 5.1 kg vs 1.6 kg on placebo.
SurvodutideHuman studies: TrialWeight loss in obesity. Positive: in SYNCHRONIZE-1 (725 adults without diabetes), weight fell 12.2–13.0% vs 5.4% on placebo at 76 weeks, counting everyone randomized. Not approved anywhere.
SurvodutideHuman studies: TrialWeight loss with type 2 diabetes. Positive: in SYNCHRONIZE-2 (752 adults), weight fell 8.2–9.8% vs 3.9% on placebo at 76 weeks, counting everyone randomized; HbA1c, a 3-month blood sugar average, fell 0.8–0.9 points vs 0.2.
MazdutideApproved drug: TrialWeight management (approved in China). Positive: approved in China since June 2025. In GLORY-1 (610 Chinese adults), weight fell 11.0% (4 mg) and 14.0% (6 mg) vs a 0.3% gain on placebo at 48 weeks, counting everyone randomized.
MazdutideApproved drug: TrialWeight loss at 9 mg. Positive: in GLORY-2 (461 Chinese adults with a BMI of 30 or more), 9 mg cut weight 16.65% vs 1.50% on placebo at 60 weeks, counting everyone dosed. Filed for approval in China.
MazdutideApproved drug: TrialWeight loss at 10–16 mg (US trial). Promising: 10 and 16 mg cut weight 15.6% and 18.1% vs 0.9% on placebo at 32 weeks in 179 US adults, if all stayed on treatment; side effects made 20% stop 16 mg.
OrforglipronApproved drug: TrialKeeping weight off after injections. Positive: after stopping tirzepatide or semaglutide, people kept 75–79% of their earlier weight loss over 52 weeks on orforglipron vs 38–49% on placebo, counting everyone randomized.
TesofensineHuman studies: TrialWeight loss in obesity. Phase 2: with a reduced-calorie diet, 0.5 mg daily for 24 weeks gave 9.2% more weight loss than placebo in 203 adults, counting all randomized people measured after a dose.
TesofensineHuman studies: TrialWeight loss: Mexican Phase 3. Positive per the developer: about 10% weight loss at 0.5 mg over 24 weeks in 372 adults on diet and exercise, with a small heart-rate rise. Not yet published in a journal.
TesofensineHuman studies: TrialHypothalamic obesity, with metoprolol. In 21 adults with obesity from hypothalamic damage, tesofensine plus metoprolol (a heart drug) for 24 weeks gave 6.3% more weight loss than placebo. Small, but positive.
TesofensineHuman studies: TrialAppetite control. In 32 overweight men, 2 weeks on it raised fullness and cut weight 1.8 kg more than placebo, mainly by curbing appetite; in a longer trial, the fullness effect waned.
DulaglutideApproved drug: TrialWeight loss. Modest, never approved for it: in type 2 diabetes, weight fell 4.6 kg on 4.5 mg vs 3.0 kg on 1.5 mg over 36 weeks (AWARD-11). It hasn’t been developed for obesity alone.
LixisenatideApproved drug: TrialWeight loss. Small, never approved for it: added to metformin, weight fell 2.7 kg vs 1.7 kg on placebo over 24 weeks. Combined with insulin glargine, weight stayed about level (a 0.3 kg loss).
PramlintideApproved drug: TrialWeight loss in obesity. Modest and never approved: with a lifestyle program, adults without diabetes lost 6–7 kg more than on placebo at 12 months, counting only those still in the trial.
SetmelanotideApproved drug: TrialObesity with single-copy gene variants. Negative per the developer: in EMANATE (295 people with one altered copy of POMC, PCSK1, LEPR, SRC1 or SH2B1), BMI didn’t fall significantly more than on placebo at 52 weeks.
SetmelanotideApproved drug: TrialCommon obesity. Not shown: in a 74-person, 90-day trial, weight fell 2.0% vs 0.3% on placebo, not a significant difference. The label says it isn’t expected to work in general obesity.
SetmelanotideApproved drug: TrialAlström syndrome. Inconclusive: in the Bardet-Biedl trial, the few people with Alström syndrome, another rare genetic obesity, showed no clear benefit; it isn’t approved for it.
PemvidutideHuman studies: TrialWeight loss in obesity. Promising but unpublished: in MOMENTUM (391 adults without diabetes), weight fell 10.3–15.6% vs 2.2% on placebo at 48 weeks, per Altimmune’s 2023 release. No obesity phase 3 has been announced.
PemvidutideHuman studies: TrialKeeping muscle during weight loss. Unproven: Altimmune reported that 25.5% of the weight lost in MOMENTUM was lean mass (press release, March 2024). No head-to-head comparison with other weight-loss drugs has been published.
Maridebart cafraglutideHuman studies: TrialWeight loss in obesity. Promising: in a 52-week phase 2 trial (465 adults without diabetes), weight fell 12.3–16.2% vs 2.5% on placebo, counting everyone randomized. Phase 3 weight trials report from 2027.
Maridebart cafraglutideHuman studies: TrialWeight loss with type 2 diabetes. Promising: in 127 adults with type 2 diabetes, weight fell 8.4–12.3% vs 1.7% on placebo at 52 weeks, and HbA1c, a 3-month blood sugar average, 1.2–1.6 points vs a 0.1 rise.
Maridebart cafraglutideHuman studies: TrialKeeping weight off with fewer doses. Promising but unpublished: Amgen says most people who lost 15% or more in year one kept it off for another year on lower monthly or every-12-week doses (February 2026).
AmycretinHuman studies: TrialWeight loss in obesity. Promising: in a 36-week phase 1b/2a injection trial (125 adults), weight fell 22.0% on 20 mg vs a 1.9% gain on placebo, in small groups. Phase 3 (AMAZE) began in February 2026.
AmycretinHuman studies: TrialWeight loss with type 2 diabetes. Promising: in the same trial, Novo Nordisk reported weight loss of up to 14.5% with injections and 10.1% with tablets vs 2.5–2.6% on placebo, if all had stayed on treatment.
AmycretinHuman studies: TrialWeight loss with a daily tablet. Early: in a 12-week phase 1 trial, Novo Nordisk reported 13.1% weight loss on 100 mg a day vs 1.1% on placebo. A 76-week phase 3 tablet trial began in August 2026.
EloralintideHuman studies: TrialWeight loss in obesity or overweight. Promising, not approved: in a 48-week phase 2 trial of 263 adults without diabetes, weekly doses cut weight 9.4–20.1% vs 0.4% on placebo, if everyone had stayed on treatment.
EloralintideHuman studies: TrialWeight loss with type 2 diabetes. Positive, not approved: in a 48-week trial of 367 adults with type 2 diabetes, it cut weight 8.2–12.3% vs 3.0% on placebo, if all stayed on treatment (press release, September 2026).
EloralintideHuman studies: TrialWeight loss with tirzepatide. With tirzepatide, weight fell up to 23.3% vs 14.8% on tirzepatide 15 mg alone at 48 weeks in type 2 diabetes, with more side effects (press release). Not approved.
PetrelintideHuman studies: TrialWeight loss in obesity or overweight. Promising, not approved: in a 42-week phase 2 trial of 493 adults without diabetes, weight fell 7.9–9.8% vs 1.7% on placebo at 28 weeks, if all stayed on treatment.
PetrelintideHuman studies: TrialWeight loss with type 2 diabetes. Positive, not approved: in a 28-week trial of 220 adults with type 2 diabetes, weight fell 7.4–9.2% vs 2.0% on placebo, if all stayed on treatment (press release, October 2026).
VK2735Human studies: TrialWeight loss in obesity or overweight. Promising, not approved: in a 13-week phase 2 trial of 176 adults without diabetes, weekly injections cut weight 9.1–14.7% vs 1.7% on placebo, if all stayed on treatment.
VK2735Human studies: TrialWeight loss with a daily tablet. Up to 12.2% vs 1.3% on placebo in 13 weeks in 280 adults, but 20% stopped for side effects vs 13% (press release, August 2025). Not approved.
VK2735Human studies: TrialKeeping weight off with less frequent doses. After 21 weekly doses, every-other-week or monthly injections kept 82–97% of the loss over 12 weeks vs 61% on placebo (press release, September 2026).
AdipotidePreclinical: TrialObesity. No published human result: the only trial, in men with metastatic prostate cancer and obesity, enrolled 4 of up to 15 planned patients and was terminated without reporting weight or safety.
CJC-1295 with DACHuman studies: TrialBelly fat in HIV. Unproven: a Phase 2 trial in people with HIV and excess belly fat was stopped in 2006 after a participant died of a heart attack; no results were published.
TesamorelinApproved drug: TrialBelly fat in obesity without HIV. Unapproved: in a 12-month trial of 60 adults with abdominal obesity and low growth hormone release, visceral fat shrank 16 cm² vs a 19 cm² gain on placebo; triglycerides fell and blood sugar held steady.
GHRP-2Approved drug: TrialIncreasing appetite. Short-term rise: 7 healthy men ate 36% more at a buffet meal during an infusion. Over a year of oral doses in 10 children, appetite rose in 7, but body mass index didn’t change significantly.
MK-677Human studies: TrialFat loss. Not shown: in 24 obese men over 8 weeks, lean mass rose but total and belly fat didn’t change. In older adults, weight rose 2.7 kg over a year vs 0.8 on placebo.
Somatropin (HGH)Approved drug: TrialFat loss in obesity. Unproven for weight loss: in trials in adults with obesity, fat fell 0.9 kg and belly fat shrank, but weight didn’t drop, fasting blood sugar rose, and joint pain and swelling increased.
OctreotideApproved drug: TrialWeight loss in obesity. Small effect, not approved: in 172 adults with obesity and high insulin output, 6 months of the depot gave about 2% more weight loss than placebo and raised blood sugar after glucose.
ACE-031Human studies: TrialFat loss. Fat mass trended down in the Duchenne trial and fat-metabolism markers shifted in the single-dose trial. No trial set out to test fat loss.
PT-141Approved drug: TrialWeight loss. Unproven: in a 16-day phase 1 trial in women with obesity, three daily injections cut food intake about 400 kcal a day and weight 1.3 kg more than placebo. A second short trial agreed.
OxytocinApproved drug: TrialWeight loss. Negative: in an 8-week trial of 61 adults with obesity, nasal oxytocin 4 times daily didn’t change weight vs placebo (0.20 vs 0.26 kg), though it cut intake at one test meal.

Seen only in animals 12

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

RetatrutideHuman studies: AnimalBoosting metabolism (extra calorie burning). Unproven in people: in obese mice, its glucagon action raised energy use on top of lower food intake. Human trials show weight loss but haven’t shown how much extra burning adds.
AOD9604Human studies: AnimalFat loss from injections. Unproven in people: obese rats and mice given it by mouth, injection or pump gained less weight and burned more fat. No human study has tested injections under the skin.
5-Amino-1MQPreclinical: AnimalFat loss and weight loss. Unproven in people: obese mice injected three times daily for 11 days lost 5.1% of body weight vs a 1.4% gain on saline, with 35% smaller fat pads, while eating the same.
SLU-PP-332Preclinical: AnimalFat loss and metabolic syndrome. Unproven in people: in obese mice it raised energy use and fat burning, cut fat gain and improved insulin sensitivity. No human study exists.
HGH Fragment 176-191Preclinical: AnimalFat loss. Unproven: no study has tested this exact peptide for fat loss. Closely related fragments (hGH 177–191 and AOD9604) cut fat-making and slowed weight gain in obese rats and mice.
HGH Fragment 176-191Preclinical: AnimalFat loss without blood sugar effects. Contradicted in rats: in a 1978 study, this fragment briefly raised blood sugar and insulin and reduced insulin sensitivity. The “no blood sugar effect” claim comes from AOD9604 research.
SurvodutideHuman studies: AnimalBurning more calories (boosting metabolism). Unproven in people: in obese mice, its glucagon action raised energy use on top of eating less. A human study comparing calorie burning with semaglutide is under way.
AdipotidePreclinical: AnimalFat loss and belly fat. Unproven in people: in obese monkeys, 4 weeks of daily injections cut body weight 7.4–14.7% and total body fat about 39%, with kidney damage at the same dose.
AdipotidePreclinical: AnimalAppetite suppression. Not what it was designed for, but treated monkeys ate less, and a 2012 letter argued this, not fat-vessel killing, explained the weight loss.
MOTS-cPreclinical: AnimalWeight loss. Unproven in people: mice on a high-fat diet gained less weight on daily injections for 8 weeks. CB4211, a modified version, showed only a trend toward lower weight in 20 adults over 4 weeks.
HumaninPreclinical: AnimalWeight and fatty liver. Unproven in people: in mice on a high-fat diet, HNG injections reduced weight gain, belly fat and fat buildup in the liver.
Melanotan 2Human studies: AnimalAppetite and weight loss. Unproven: men reported less appetite after single doses (1998), and rats given it into the brain ate 30% less at first and lost body fat. No weight-loss study in people exists.

Claims without data 11

Promoted by sellers, clinics or users, with no study behind the claim.

5-Amino-1MQPreclinical: CommunityFat loss and energy in people. Unproven: users report fat loss and more energy, but no published study has given it to a person at any dose.
SLU-PP-332Preclinical: CommunityEndurance and fat loss in people. Unproven: users describe better endurance, recovery and leanness, but no published study has given it to a person.
HGH Fragment 176-191Preclinical: No studyWeight loss in people. Unproven: never tested in people. AOD9604, a related peptide whose sequence these vials often list, didn’t beat placebo for weight loss in a 24-week, 502-person trial.
SetmelanotideApproved drug: No studyPrader-Willi syndrome. Unproven: an 18-person phase 2 trial in this genetic cause of constant hunger is under way, with no results yet.
EloralintideHuman studies: No studyGentler on the stomach than GLP-1 drugs. Unproven: no trial has compared them head to head. In phase 2, nausea hit 11–64% depending on dose and starting schedule, and fatigue up to 46%.
PetrelintideHuman studies: No studyCombined with a GLP-1 drug. Unproven: no results exist. A phase 2 trial of petrelintide with enicepatide, an experimental GLP-1 and GIP drug, was due to start in late 2026.
PetrelintideHuman studies: No studyGentler on the stomach than GLP-1 drugs. Unproven: no head-to-head trial exists. In phase 2, nausea hit 20% vs 6% on placebo, while vomiting and diarrhea were no more common than on placebo.
VK2735Human studies: No studyWeight loss with type 2 diabetes. Unproven: a 78-week phase 3 trial in about 1,000 adults with type 2 diabetes (VANQUISH 2) is under way and due to finish in mid-2027.
IGF-1 LR3Preclinical: CommunityFat loss and body recomposition. Unproven: widely promoted for getting leaner, but no human study exists. In growing rats, it increased weight gain while body proportions stayed about the same.
GHRP-6Human studies: CommunityAppetite and weight gain. Unproven: users take it for strong hunger, but no human study has measured appetite on GHRP-6. GHRP-2, which acts on the same receptor, raised food intake 36% in 7 men.
Kisspeptin-10Human studies: No studyWeight loss. Unproven: FDA found clinics promoting kisspeptin products for weight loss, but no human study has tested kisspeptin-10 for weight; FDA received one report of weight gain.

Blood sugar and diabetes 45

On a label 12

Approved uses, from a product label somewhere in the world.

SemaglutideApproved drug: LabelType 2 diabetes. Ozempic (weekly) and Rybelsus or Ozempic tablets (daily) are approved for adults. In a 30-week trial, HbA1c, a 3-month blood sugar average, fell 1.4–1.6 points vs 0.1 on placebo.
TirzepatideApproved drug: LabelType 2 diabetes. Mounjaro is approved for adults and children 10 and older. In a 40-week trial, HbA1c, a 3-month blood sugar average, fell 1.7–1.8 points vs 0.1 on placebo.
LiraglutideApproved drug: LabelType 2 diabetes. Victoza and generic pens are approved for adults and children 10 and older. Added to metformin for 26 weeks, HbA1c, a 3-month blood sugar average, fell 1.0 point vs a 0.1 rise on placebo.
ExenatideApproved drug: LabelType 2 diabetes. Approved for adults; only a generic twice-daily pen is still sold in the US. Alone for 24 weeks, HbA1c, a 3-month blood sugar average, fell 0.9 points on 10 mcg vs 0.2 on placebo.
OrforglipronApproved drug: LabelType 2 diabetes (blood sugar control). Approved for this in the UK (August 2026), not yet in the US. In ACHIEVE-1, HbA1c, a 3-month blood sugar average, fell 1.24–1.48 points vs 0.41 on placebo over 40 weeks.
DulaglutideApproved drug: LabelType 2 diabetes. Trulicity is approved for adults and children 10 and older. Added to metformin for 26 weeks, HbA1c, a 3-month blood sugar average, fell 1.0–1.2 points vs a 0.1 rise on placebo.
LixisenatideApproved drug: LabelType 2 diabetes. Approved for adults, alone (withdrawn in the US and EU) or in Soliqua with insulin glargine. Over 30 weeks, HbA1c, a 3-month blood sugar average, fell 1.6 points on the combination vs 1.3 on glargine.
EcnoglutideApproved drug: LabelType 2 diabetes. Approved in China since January 2026. In EECOH-1 (211 adults), HbA1c, a 3-month blood sugar average, fell 1.96–2.43 points vs 0.87 on placebo at 24 weeks; it slightly beat dulaglutide in EECOH-2.
PramlintideApproved drug: LabelType 1 diabetes, with mealtime insulin. Approved for this, though no longer sold in the US. Over 6 months, HbA1c, a 3-month blood sugar average, fell 0.25–0.34 points more than with insulin alone.
PramlintideApproved drug: LabelType 2 diabetes, with mealtime insulin. Approved for this, though no longer sold in the US. Over 6 months, 120 mcg before meals lowered HbA1c 0.30–0.34 points more than placebo, with 1.4–1.6 kg weight loss.
GlucagonApproved drug: LabelSevere low blood sugar in diabetes. Approved as kits, Gvoke and Baqsimi. In clinic trials in adults with insulin-induced lows, 97–100% recovered within 30 minutes, on average in 10–16 minutes.
DasiglucagonApproved drug: LabelSevere low blood sugar in diabetes. Zegalogue is approved for adults and anyone with diabetes weighing at least 20 kg. In two adult trials, median recovery took 10 minutes vs 35–40 minutes on placebo.

Tested in people 27

Studied in people, whatever the result: some worked, many didn’t or are unproven.

SemaglutideApproved drug: TrialType 1 diabetes, added to insulin. Promising, not an approved use: in a 26-week trial of 72 adults with type 1 diabetes and obesity using automated insulin pumps, 36% on semaglutide vs none on placebo reached a combined goal of good glucose control, little low blood sugar and 5% weight loss. Weight fell 8.8 kg more.
TirzepatideApproved drug: TrialPreventing type 2 diabetes. Positive, not an approved use: over 176 weeks in SURMOUNT-1, 1.3% of adults with prediabetes and obesity on tirzepatide developed type 2 diabetes vs 13.3% on placebo.
TirzepatideApproved drug: TrialType 1 diabetes, added to insulin. Promising, not an approved use: in a 12-week trial of 24 adults with type 1 diabetes and obesity, weight fell 10.3 kg vs 0.7 kg on placebo, and daily insulin needs fell by about a third compared with placebo.
RetatrutideHuman studies: TrialBlood sugar in type 2 diabetes. Positive: in a 40-week trial of 537 adults managing diabetes with diet and exercise, HbA1c, a 3-month blood sugar average, fell 1.69–1.94 points vs 0.81 on placebo.
CagrilintideHuman studies: TrialBlood sugar in type 2 diabetes. Positive for the pair: in REIMAGINE 2, HbA1c fell 1.91 points vs 1.75 on semaglutide alone at 68 weeks. Cagrilintide alone lowered HbA1c 0.9 points in a 32-week trial of 30 people.
LiraglutideApproved drug: TrialPreventing type 2 diabetes. Positive, not an approved use: among 2,254 adults with prediabetes and excess weight, 2% on 3 mg daily vs 6% on placebo were diagnosed with diabetes over 160 weeks. Only half finished.
LiraglutideApproved drug: TrialType 1 diabetes, added to insulin. Mixed, not approved for this: in ADJUNCT ONE (1,398 adults, 52 weeks), 1.8 mg lowered HbA1c, a 3-month blood sugar average, 0.20 points and weight 4.9 kg more than placebo, but symptomatic low blood sugar was 31% more common and high blood sugar with ketones more than twice as common.
MazdutideApproved drug: TrialType 2 diabetes (approved in China). Positive: approved in China since September 2025. HbA1c, a 3-month blood sugar average, fell 1.57–2.15 points vs 0.14 on placebo at 24 weeks (DREAMS-1, 320 adults), and more than on dulaglutide (DREAMS-2).
OrforglipronApproved drug: TrialCompared with other diabetes pills. Positive: HbA1c fell more than with oral semaglutide over 52 weeks (1.91 vs 1.47 points at top doses) or dapagliflozin over 40 weeks (1.56 vs 0.81).
PramlintideApproved drug: TrialType 2 diabetes on basal insulin only. Positive but unapproved: added to insulin glargine for 16 weeks in 212 adults, HbA1c fell 0.70 vs 0.36 points on placebo, and weight fell 1.6 kg vs a 0.7 kg gain.
PramlintideApproved drug: TrialAutomated insulin pumps (artificial pancreas). Early signal: in a small 24-hour crossover study in type 1 diabetes, adding pramlintide to rapid insulin in a closed-loop system raised time in target range from 74% to 84%.
GlucagonApproved drug: TrialPreventing lows during exercise. Promising, unproven: in a 15-adult crossover trial in type 1 diabetes, a small dose before fasting exercise prevented lows (none vs 6 people without treatment). Not an approved use.
DasiglucagonApproved drug: TrialLow blood sugar after gastric bypass. Unapproved: in a 4-week crossover trial of 24 adults, self-injected low doses cut time below 70 mg/dL by 33% vs placebo and corrected 97% of lows within 15 minutes.
DasiglucagonApproved drug: TrialMild lows in type 1 diabetes. Unproven: in a 2-week trial of 24 adults, low doses by pen sped recovery from lows by 44% and cut carbohydrate eaten by 11%; time spent low didn’t differ significantly.
DasiglucagonApproved drug: TrialDual-hormone insulin pumps. Experimental: in a 7-day home crossover of 10 adults, a pump adding dasiglucagon to insulin kept glucose in range 79% of the time vs 72% with insulin alone.
Maridebart cafraglutideHuman studies: TrialType 2 diabetes (blood sugar control). Promising but unpublished: in a 24-week phase 2 trial of 409 adults, Amgen reported clinically meaningful falls in HbA1c and weight (February 2026) without giving numbers. Phase 3 diabetes trials start in 2026.
AmycretinHuman studies: TrialType 2 diabetes (blood sugar control). Positive: in a 36-week phase 2 trial (448 adults), HbA1c fell up to 1.7 points with weekly injections and 1.4 with daily tablets, significantly more than on placebo.
EloralintideHuman studies: TrialBlood sugar in type 2 diabetes. In the same trial, HbA1c (average blood sugar) fell 1.1–1.4 points vs 0.3 on placebo at 48 weeks. Reported by press release only; not yet published.
PetrelintideHuman studies: TrialBlood sugar in type 2 diabetes. In the same trial, HbA1c (average blood sugar) fell up to 0.65 points vs a 0.23 rise on placebo at 28 weeks. Press release only; not yet published.
PancragenPreclinical: TrialType 2 diabetes in older adults. One small 2011 study: in 33 older people with type 2 diabetes, fasting glucose, insulin and insulin resistance fell with pancragen but not without it. No numbers, randomization or blinding reported.
PancragenPreclinical: TrialPrediabetes (impaired glucose tolerance). In a 2013 study, 12 older adults given 500 mcg twice daily for 4 weeks improved on glucose tests in half the cases. No control group, so unproven.
CarnosineHuman studies: TrialBlood sugar in prediabetes and type 2 diabetes. Mixed: 1–2 g daily for 12–14 weeks lowered fasting or post-glucose-drink sugar in small trials (30–54 people); a 49-person trial found no change in blood pressure, lipids or arteries.
ARA-290Human studies: TrialBlood sugar control in type 2 diabetes. Unproven: in the same 48-person trial HbA1c, a 3-month blood sugar average, fell 0.21 points by day 56 while rising 0.21 on placebo. No larger trial has confirmed it.
MecaserminApproved drug: TrialType 2 diabetes. Not pursued: in 12 adults HbA1c fell from 10.4% to 8.1% over 6 weeks, but swelling, jaw and joint pain and fast heartbeat forced stops; in another study, all 7 stopped early.
MecaserminApproved drug: TrialType 1 diabetes, alongside insulin. Unproven: in a 12-week trial of 223 people aged 11–66, adding it cut HbA1c 1.2 points vs 0.7 with insulin alone. No trials continue, partly over diabetic eye disease concerns.
MecaserminApproved drug: TrialSevere inherited insulin resistance. Small pilot studies in conditions such as Rabson-Mendenhall syndrome and type A insulin resistance found lower glucose and insulin and better HbA1c. It isn’t approved for this.
VilonPreclinical: TrialType 1 diabetes: clotting and insulin needs. Unproven: two small Russian reports said adding it to standard care improved clotting markers and cut insulin needs in most patients; the abstracts give no patient numbers, doses or comparison groups.

Seen only in animals 6

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

PancragenPreclinical: AnimalBlood sugar control in aging. In old rhesus monkeys (2014–2015 studies), a 10-day course improved glucose tolerance and normalized insulin; in diabetic rats it lowered blood sugar and partly restored insulin production.
AdipotidePreclinical: AnimalInsulin resistance. Unproven in people: a measure of insulin resistance fell about 49% in treated obese monkeys while rising about 34% in untreated ones, and glucose tolerance improved in obese mice.
AdipotidePreclinical: AnimalType 2 diabetes. Unproven: in obese mice the effect on glucose tolerance appeared within days and held even when weight and food intake were matched. No human study exists.
MOTS-cPreclinical: AnimalBlood sugar and insulin resistance. Unproven in people: it prevented diet- and age-related insulin resistance in mice, and CB4211 cut glucose 6% vs 0% on placebo in 4 weeks.
HumaninPreclinical: AnimalBlood sugar and insulin resistance. Unproven in people: infused into the brain or blood of rats, it improved insulin action, and one dose of a stronger version (HNG) lowered blood sugar in diabetic rats.
PE-22-28Preclinical: AnimalBlood sugar and insulin-cell health. Unproven: in cell studies, PE-22-28 protected insulin-making pancreatic cells from inflammatory damage and helped them multiply (2021). It hasn’t been tested for diabetes in people.

Heart and blood vessels 33

On a label 6

Approved uses, from a product label somewhere in the world.

SemaglutideApproved drug: LabelLowering heart attack and stroke risk. Approved for heart disease with excess weight (Wegovy) or type 2 diabetes at high heart risk (Ozempic, Rybelsus). In SELECT, heart attack, stroke or heart death: 6.5% vs 8.0% on placebo over 3+ years.
TirzepatideApproved drug: LabelLowering heart attack and stroke risk. Mounjaro is approved for type 2 diabetes at high heart risk. In SURPASS-CVOT, heart attack, stroke or heart death hit 12.2% vs 13.1% on dulaglutide, itself approved for this: not worse, not shown better.
LiraglutideApproved drug: LabelLowering heart attack and stroke risk. Victoza is approved for adults with type 2 diabetes and heart or blood vessel disease. In LEADER (9,340 adults), heart attack, stroke or heart death: 13.0% vs 14.9% on placebo.
DulaglutideApproved drug: LabelLowering heart attack and stroke risk. Approved for adults with type 2 diabetes and heart disease or several risk factors. In REWIND (9,901 adults, median 5.4 years), heart attack, stroke or heart death: 12.0% vs 13.4% on placebo.
EnlicitideApproved drug: LabelHigh LDL cholesterol. Approved for adults, with diet and exercise, usually on top of a statin. In CORALreef Lipids (2,904 adults), LDL fell 57% vs a 3% rise on placebo at 24 weeks.
EnlicitideApproved drug: LabelInherited high cholesterol (HeFH). Covered by the approval. In 303 adults already on statins, 64% also on ezetimibe, LDL fell 58.2% vs a 2.6% rise on placebo at 24 weeks.

Tested in people 17

Studied in people, whatever the result: some worked, many didn’t or are unproven.

TirzepatideApproved drug: TrialHeart failure with obesity (HFpEF). Positive, not approved: in SUMMIT (731 adults with obesity and HFpEF, a stiff-heart type of heart failure), heart death or worsening heart failure hit 9.9% vs 15.3% on placebo over a median 2 years.
ExenatideApproved drug: TrialLowering heart attack and stroke risk. Not shown: in EXSCEL (14,752 adults with type 2 diabetes, median 3.2 years), heart attack, stroke or heart death: 11.4% on the weekly form vs 12.2% on placebo; no added risk, no significant benefit.
OrforglipronApproved drug: TrialHeart safety in type 2 diabetes. Reassuring: in ACHIEVE-4 (2,749 adults at high heart risk), heart attack, stroke, heart death or unstable angina hit 4.2% vs 5.0% on insulin glargine over a median 2 years.
LixisenatideApproved drug: TrialLowering heart attack and stroke risk. Not shown: in ELIXA (6,068 adults with type 2 diabetes and a recent heart attack or unstable angina), heart events hit 13.4% vs 13.2% on placebo over 25 months: no harm, no benefit.
EnlicitideApproved drug: TrialCompared with other cholesterol pills. Positive: over 8 weeks in 301 adults on statins, LDL fell 64.6% vs 27.8% with ezetimibe, 6.3% with bempedoic acid and 36.5% with both.
EnlicitideApproved drug: TrialLowering lipoprotein(a). Modest: in the HeFH trial, lipoprotein(a), an inherited heart-risk particle, fell a median 24.7% vs 1.6% on placebo. Whether that lowers heart risk is unknown.
GlucagonApproved drug: TrialBeta-blocker overdose. Unproven: a 2020 systematic review found only case reports and case series, where glucagon modestly raised heart rate, and no controlled trials.
Maridebart cafraglutideHuman studies: TrialHeart disease and heart failure. Unproven: MARITIME-CV (about 12,800 adults) and MARITIME-HF (about 5,000) are testing whether it prevents heart attacks, strokes or heart failure events; completion is expected in 2030.
AmycretinHuman studies: TrialHeart failure with obesity. Unproven: HF-POLARIS (about 5,600 adults with heart failure with preserved or mildly reduced pumping) is testing whether weekly injections reduce heart failure events; results are expected in late 2029.
VK2735Human studies: TrialBlood pressure. Systolic pressure fell 6.7–11.0 mmHg vs 4.2 on placebo over 13 weeks, a secondary measure in a short trial, not a confirmed benefit.
SS-31Approved drug: TrialHeart failure and heart attack. Negative: 4 weeks of injections didn’t improve heart pumping in 71 people with heart failure, and a 1-hour IV infusion during heart-attack treatment didn’t shrink heart damage in 300 people.
GlutathioneApproved drug: TrialLeg artery disease (walking pain). Small trial: in 40 people with peripheral artery disease, 5 days of twice-daily IV glutathione raised pain-free walking from 143 to 196 meters; saline didn’t change it.
VesugenPreclinical: TrialPeripheral artery disease after surgery. Unproven: in 41 adults after surgery for chronic leg artery disease, blood flow improved after a Vesugen course, but there was no comparison group and the abstract gives no numbers.
CarnosineHuman studies: TrialHeart failure. Unconfirmed: in an open-label trial of 50 people with heart failure, 500 mg daily for 6 months improved walking distance, peak oxygen uptake and quality of life vs standard care.
Thymosin Beta-4Human studies: TrialHeart attack recovery. Unproven: in a 96-person Chinese trial of an IV recombinant form after an artery-opening procedure, heart scar size at 90 days didn’t differ overall, but was smaller with dosing within 8 hours.
HexarelinHuman studies: TrialHeart pumping strength in heart failure. Unproven: single IV doses briefly raised heart pumping strength in 7 healthy men and 5 heart-failure patients with blocked arteries, but not in 8 with an enlarged, weak heart. Repeated use is untested.
DesmopressinApproved drug: TrialReducing blood loss in surgery. Not shown for most people: a Cochrane review of 65 trials (3,874 people) without bleeding disorders found little or no difference in how many needed transfusions.

Seen only in animals 7

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

SLU-PP-332Preclinical: AnimalHeart failure. Unproven in people: in mice with pressure-overloaded hearts, it improved pumping strength, reduced scarring and raised survival. It has never been tested in a person.
HumaninPreclinical: AnimalHeart protection. Unproven in people: in mice, HNG given before or as blood flow returned to a blocked heart artery shrank the damage and preserved pumping a week later.
CardiogenPreclinical: AnimalHeart attack recovery. Unproven in people: its developers report, citing their patent, three times fewer deaths and smaller damaged areas in rats after an induced heart attack.
CardiogenPreclinical: AnimalHeart muscle aging. Unproven: in heart tissue from young and old rats grown in a dish, it strongly stimulated cell growth and lowered p53, a cell-death signal.
MGFPreclinical: AnimalHeart protection after a heart attack. Unproven in people: given around an induced heart attack, it preserved the heart’s pumping in sheep (2008) and mice (2013, 2015). It has never been tested in humans.
GHRP-6Human studies: AnimalHeart protection after a heart attack. Unproven in people: in a pig model of heart attack, one high IV dose cut the mass of dead heart muscle by 78%. No human trial of this use has been published.
HexarelinHuman studies: AnimalHeart protection after a heart attack. Unproven in people: in mice with induced heart attacks, 21 days of daily hexarelin preserved heart function and reduced scarring of heart muscle. No human trial has tested this.

Claims without data 3

Promoted by sellers, clinics or users, with no study behind the claim.

EnlicitideApproved drug: No studyPreventing heart attacks and strokes. Unproven so far: CORALreef Outcomes, in about 14,550 high-risk adults, is under way. The label notes that lowering LDL cut such events in trials of statins and injected PCSK9 drugs.
CardiogenPreclinical: No studyChronic coronary heart disease. Unproven: the Russian supplement is promoted for chronic coronary heart disease, but no human study of Cardiogen has been published.
TB-500Preclinical: No studyHeart repair after a heart attack. Unproven: the heart studies, including a Chinese trial in 96 patients, used full-length thymosin beta-4, a different molecule. No study has tested TB-500 for the heart.

Liver 21

On a label 3

Approved uses, from a product label somewhere in the world.

SemaglutideApproved drug: LabelMASH, a fatty liver disease. Wegovy is approved, pending confirmation, for MASH with moderate to advanced scarring, without cirrhosis. At 72 weeks, liver inflammation resolved in 63% vs 34% on placebo; scarring improved in 37% vs 22%.
OctreotideApproved drug: LabelBleeding varices in liver cirrhosis. A UK label use, alongside endoscopic treatment. Added to sclerotherapy, it raised 5-day survival without rebleeding to 87% from 71% in 199 people, but reviews found no clear effect on deaths.
Thymosin Alpha-1Approved drug: LabelChronic hepatitis B. Approved in countries such as Indonesia and India: 1.6 mg twice weekly for 6 months. Trials disagree: complete response 40.6% vs 9.4% untreated in one; 14% vs 4% on placebo, not significant, in another.

Tested in people 14

Studied in people, whatever the result: some worked, many didn’t or are unproven.

TirzepatideApproved drug: TrialMASH, a fatty liver disease. Promising, not approved: in a 52-week phase 2 trial of 190 adults with MASH and liver scarring, MASH resolved without worse scarring in 44–62% vs 10% on placebo. An outcomes trial is under way.
RetatrutideHuman studies: TrialFatty liver (MASLD). Promising: in a 98-person phase 2 substudy, liver fat fell 42.9–82.4% at 24 weeks vs no change on placebo, reaching normal levels in up to 86%. Liver outcome trials are under way.
LiraglutideApproved drug: TrialMASH, a fatty liver disease. Promising but small, not approved: in a 48-week trial, the disease (then called NASH) resolved in 9 of 23 people on 1.8 mg vs 2 of 22 on placebo, and fewer had worsening scarring.
SurvodutideHuman studies: TrialMASH, fatty liver with inflammation. Promising: in a 48-week phase 2 trial of 293 adults with MASH and liver scarring, MASH improved without worse scarring in 43–62% vs 14% on placebo. Phase 3 outcome trials are under way.
SurvodutideHuman studies: TrialLiver fat in obesity (MASLD). Positive: in SYNCHRONIZE-MASLD (216 adults), liver fat fell by at least 30% in 68.5% vs 28.6% on placebo at 48 weeks, counting everyone treated; 84.2% vs 24.3% if all had stayed on treatment.
SurvodutideHuman studies: TrialCirrhosis from fatty liver disease. Unproven: in an open-label study without placebo, 41 people with overweight, with or without cirrhosis, took it for 28 weeks; liver fat, liver stiffness and weight generally fell. Outcome trials are under way.
MazdutideApproved drug: TrialFatty liver (MASLD). Unproven: pooled trials show lower liver enzymes, and in obese mice it reduced liver fat. A phase 3 trial against semaglutide in 479 adults with fatty liver disease is under way.
PemvidutideHuman studies: TrialMASH, fatty liver with inflammation. Promising: in IMPACT (212 adults with MASH and F2–F3 scarring), MASH cleared without worse scarring in 52–58% vs 20% on placebo at 24 weeks, but scarring didn’t improve more than on placebo.
PemvidutideHuman studies: TrialLiver fat in fatty liver disease (MASLD). Positive: in a 12-week trial of 94 adults, liver fat fell 47–69% vs 4% on placebo; in a 24-week extension (64 people) it fell 56–76% vs 14%.
PemvidutideHuman studies: TrialAlcohol-related liver disease. Unproven: RESTORE, a 48-week placebo-controlled trial in about 120 adults, finished enrolling in July 2026; results are expected in the second half of 2027.
MOTS-cPreclinical: TrialFatty liver disease. Unproven: its modified version CB4211 lowered ALT, a liver enzyme, 21% while it rose 4% on placebo in 20 adults over 4 weeks, but liver fat fell as much on placebo. Company data only.
GlutathioneApproved drug: TrialFatty liver disease. Unproven: in an open study without placebo, 29 people with fatty liver took oral glutathione for 4 months after diet changes, and the liver enzyme ALT fell.
TesamorelinApproved drug: TrialLiver fat in HIV. Unapproved: in a 12-month trial of 61 people with HIV and fatty liver, liver fat fell 4.1 percentage points more than on placebo. A trial in 51 people without HIV hasn’t been published.
MK-677Human studies: TrialFatty liver disease. Not shown: in an uncontrolled 6-month study of 12 adults with fatty liver, liver fat didn’t fall (it rose 3.9 points on average, not significant). Results are posted, not published.

Seen only in animals 2

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

5-Amino-1MQPreclinical: AnimalBlood sugar and fatty liver. Unproven in people: in obese mice given daily injections for 28 days, glucose tolerance and insulin sensitivity improved and liver fat fell, in a study by the developer’s team.
LivagenPreclinical: AnimalLiver protection and liver disease. Unproven in people. It aided rat liver cells and tissue in culture, and a 2020 developer review says it and a calf-liver extract protected the liver in animal hepatitis models. No human study exists.

Claims without data 2

Promoted by sellers, clinics or users, with no study behind the claim.

LivagenPreclinical: No studyDetox. No study has measured detoxification, a common guide claim, in people or animals.
OvagenPreclinical: No studyLiver protection and liver fibrosis. Unproven: it’s sold for the liver, and its developers’ 2021 review lists liver protection, but no liver study of this peptide appears in PubMed, in animals or people.

Muscles, bones and joints 90

In more detail: peptides for joint pain and arthritis.

In more detail: peptides for muscle growth.

On a label 9

Approved uses, from a product label somewhere in the world.

SS-31Approved drug: LabelMuscle strength in Barth syndrome. Forzinity is approved, pending confirmation, from 30 kg. Strength barely changed in the 12-week randomized phase; in an uncontrolled extension (8 patients), knee strength rose a median 63 newtons by week 168.
TeriparatideApproved drug: LabelOsteoporosis in postmenopausal women. Approved for women at high fracture risk. Over a median 19 months, new spine fractures fell to 5.0% from 14.3% on placebo, and other fragility fractures to 2.6% from 5.5%.
TeriparatideApproved drug: LabelOsteoporosis in men. Approved to raise bone mass in men with primary or low-testosterone osteoporosis. Spine density rose 5.9% vs 0.5% on placebo over a median 10 months; fractures weren’t the measured outcome.
TeriparatideApproved drug: LabelOsteoporosis from long-term steroid use. Approved for adults on at least 5 mg of prednisone a day or equivalent. Over 18 months, spine density rose 7.2% vs 3.4% on alendronate, with fewer spine fractures (0.6% vs 6.1%).
AbaloparatideApproved drug: LabelOsteoporosis in postmenopausal women. Approved for women at high fracture risk. In ACTIVE, new spine fractures hit 0.6% vs 4.2% on placebo over 18 months, and other fractures 2.7% vs 4.7%.
AbaloparatideApproved drug: LabelOsteoporosis in men. Approved in the US in 2022 to raise bone density. In 228 men, spine density rose 8.5% vs 1.2% on placebo over 12 months; fractures weren’t studied.
CalcitoninApproved drug: LabelPaget’s disease of bone. Approved as an injection when other treatments don’t work or don’t suit. In open-label trials, about 2 in 3 patients had a 30%+ fall in bone-turnover markers, and a similar share had less bone pain.
CalcitoninApproved drug: LabelOsteoporosis in postmenopausal women. US only, when other treatments aren’t suitable; the label says fracture reduction isn’t shown. In PROOF, 200 units of nasal spray daily cut new spine fractures 33% over 5 years; 100 and 400 units didn’t.
CalcitoninApproved drug: LabelBone loss after sudden immobilization. Licensed in the UK and EU for 2–4 weeks, for example after a recent osteoporotic fracture, to slow rapid bone loss. Not an approved use in the US.

Tested in people 35

Studied in people, whatever the result: some worked, many didn’t or are unproven.

SemaglutideApproved drug: TrialKnee arthritis pain. Positive, not an approved use: in STEP 9 (407 adults with obesity and knee osteoarthritis), knee pain scores fell 41.7 points vs 27.5 on placebo at 68 weeks, with weight down 13.7% vs 3.2%.
RetatrutideHuman studies: TrialKnee osteoarthritis pain. Positive: among 574 TRIUMPH-1 adults with knee arthritis, the pain score (10-point scale) fell 3.2–3.6 points vs 1.9 on placebo. A dedicated knee trial hasn’t published results.
L-CarnitineApproved drug: TrialHigh-intensity exercise performance. Mixed: a review of 11 small oral studies found 2–4 g helped some high-intensity tests but not moderate exercise. No trial has tested injections for performance.
L-CarnitineApproved drug: TrialMuscle soreness after exercise. Possible: a meta-analysis of 7 small oral trials found less soreness up to 96 hours after exercise and lower muscle-damage markers at 24 hours. Injections weren’t tested.
L-CarnitineApproved drug: TrialRheumatoid arthritis, added to standard drugs. Unproven: in a 12-week trial of 46 people with active rheumatoid arthritis, those taking 500 mg twice daily by mouth with their usual drugs ended with lower disease activity and pain scores than those on usual drugs alone, but there was no placebo and the groups differed at the start.
AmycretinHuman studies: TrialKnee osteoarthritis pain. Unproven: AMAZE 5 and 6 (about 400 adults each) are testing weight loss and knee pain with weekly injections; main results are expected in August 2028.
SS-31Approved drug: TrialMitochondrial muscle disease. Negative: in MMPOWER-3, 218 adults with primary mitochondrial myopathy, 24 weeks of daily injections didn’t improve walking distance (−3.2 m vs placebo) or fatigue. A trial in one genetic subgroup awaits results.
SS-31Approved drug: TrialMuscle energy in older adults. Unproven: one IV infusion briefly raised peak energy (ATP) output in a hand muscle in a placebo-controlled trial of 39 older adults; fatigue didn’t change. A 4-week pilot is under way.
CarnosineHuman studies: TrialExercise performance and endurance. Mostly negative: in 299 adults, 2 g daily for 12 weeks didn’t change grip strength, gait speed or most endurance tests; small gains appeared only in some age and sex subgroups.
BPC-157Preclinical: TrialKnee pain. Unproven: in a clinic chart review, 11 of 12 people given BPC-157 alone by injection into the knee joint reported relief when phoned 6–12 months later. No control group.
Thymosin Beta-4Human studies: TrialInjury and joint repair. Unproven: the only human report is a clinic chart review in which 3 of 4 people given knee injections of it with BPC-157 reported relief. No control group; injection under the skin is untested.
TeriparatideApproved drug: TrialFaster fracture healing. Unproven: in 102 women with wrist fractures, 8 weeks of 40 mcg didn’t speed healing vs placebo; 20 mcg did only in a post hoc look (7.4 vs 9.1 weeks). Not an approved use.
TeriparatideApproved drug: TrialBrittle bone disease (osteogenesis imperfecta). Negative: in 350 adults, 2 years of daily teriparatide followed by zoledronic acid raised bone density but didn’t reduce fractures (36.9% vs 36.4% with standard care).
TeriparatideApproved drug: TrialBone loss from gum disease. Small trial: in 40 adults having surgery for severe periodontitis, 6 weeks of 20 mcg daily gave more jawbone regrowth at 1 year than placebo (29% vs 3% linear gain).
AbaloparatideApproved drug: TrialAdvantages over teriparatide. Not settled: ACTIVE’s open-label teriparatide group also had fewer spine fractures than placebo, and the trial wasn’t designed to compare the two. High calcium was less common on abaloparatide (3.4% vs 6.4%).
AbaloparatideApproved drug: TrialFaster fracture healing. Not shown: in 48 older adults with pelvic fractures, 3 months of abaloparatide didn’t improve healing on CT scans, pain or mobility vs placebo.
AbaloparatideApproved drug: TrialSkin patch instead of injections. Fell short: a daily microneedle patch raised spine density 7.1% vs 10.9% with injections in 511 women over 12 months, missing its noninferiority goal. Not approved.
CalcitoninApproved drug: TrialPain from a recent spine fracture. Positive short term: across 13 small trials (589 people), calcitonin eased pain from recent osteoporotic spine fractures within a week. It didn’t help chronic pain from older fractures. Not an approved use.
CalcitoninApproved drug: TrialKnee osteoarthritis. Negative: two 2-year trials of oral calcitonin tablets in 2,206 people didn’t slow joint-space narrowing on X-ray. The tablets were never approved.
SermorelinHuman studies: TrialAnti-aging, muscle and fat loss. Unproven: in 11 healthy men aged 64–76, 6 weeks of nightly shots didn’t change weight, muscle or fat, though 2 of 6 strength tests improved. There was no placebo group.
HexarelinHuman studies: TrialMuscle, fat loss and bone. Negative: 16 weeks of twice-daily injections in 12 healthy older adults didn’t change IGF-1, body fat, lean mass or bone density, and the GH response faded by about 45%.
MK-677Human studies: TrialMuscle in older adults. Lean mass, not strength: in a year-long trial of 65 healthy adults aged 60–81, lean mass rose 1.1 kg vs a 0.5 kg loss on placebo, but strength and function didn’t improve.
MK-677Human studies: TrialBone density in osteoporosis. Mostly negative: alone it didn’t raise bone density vs placebo in 292 older women; added to alendronate, hip density rose 4.2% vs 2.5% at 18 months.
MK-677Human studies: TrialRecovery after hip fracture. Negative: in 123 older adults, IGF-1 rose but most function tests didn’t improve, and the trial stopped early over heart failure (4 of 62 vs 1 of 61 on placebo).
Follistatin-344Preclinical: TrialMuscle in Becker muscular dystrophy. Gene therapy, not the protein: in 6 patients given the FS344 gene in both thighs, 4 walked 29–125 m further and 2 didn’t change, with no placebo group.
Follistatin-344Preclinical: TrialMuscle in inclusion body myositis. Gene therapy, not the protein: in 6 patients walking distance changed by +56.0 m a year against −25.8 m in 8 untreated matched people. No randomization.
Follistatin-344Preclinical: TrialTargeted growth of one muscle. An engineered follistatin drug, ACE-083, enlarged the muscle it was injected into: up to 14.5% in 58 healthy women and 16.4% over placebo in muscular dystrophy, without consistent function gains.
Follistatin-344Preclinical: TrialAnti-aging and strength in healthy adults. Unproven: two open-label studies abroad gave 43 and 14 adults a follistatin gene on a plasmid and measured blood levels and body scans, but reported no results.
Somatropin (HGH)Approved drug: TrialMuscle and athletic performance. Unproven: across trials in 303 fit young adults, lean mass rose 2.1 kg, much of it water, but strength and exercise capacity didn’t improve. One 8-week trial found sprint capacity up 3.9%.
MecaserminApproved drug: TrialMuscle, strength or anti-aging. Unproven: in 16 healthy women over 60, a year of IGF-1 raised blood IGF-1 about fivefold but didn’t change lean mass, strength or bone density. No trial tested bodybuilding use.
ACE-031Human studies: TrialBuilding muscle mass. One injection raised lean body mass 3.3% and thigh muscle volume 5.1% after a month in 48 healthy postmenopausal women, at the top dose only. Strength wasn’t measured.
ACE-031Human studies: TrialBone density. Blood markers of bone metabolism shifted in the single-dose trial and bone density trended up in the Duchenne trial, but no trial tested fractures or bone disease.
OxytocinApproved drug: TrialFibromyalgia. Negative: in a crossover trial of 14 women, 3 weeks of nasal oxytocin (80 IU a day) didn’t ease pain, anxiety, low mood or sleep problems more than placebo.
IcotrokinraApproved drug: TrialPsoriatic arthritis. Unproven so far: two phase 3 trials in about 1,300 adults are under way, and no results had been reported by October 2026.
ThymulinHuman studies: TrialRheumatoid arthritis. Two randomized placebo-controlled trials in 1987 found 5 mg a day best: 56% of patients rated improved against 17% on placebo, with minimal side effects. Never developed further.

Seen only in animals 23

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

AOD9604Human studies: AnimalKnee osteoarthritis and cartilage repair. Unproven in people: in a 32-rabbit study of damaged knees, weekly joint injections improved cartilage, more so with hyaluronic acid (a joint lubricant). FDA found no human osteoarthritis study.
5-Amino-1MQPreclinical: AnimalMuscle strength in aging. Unproven in people: aged mice given daily injections for 8 weeks had about 40% greater grip strength than untreated controls, and injured muscle regrew faster in older mice.
5-Amino-1MQPreclinical: AnimalKeeping muscle while dieting. Unproven in people: obese mice switched to a lean diet lost more fat, with a higher share of lean mass, when it was added. It hasn’t been tested alongside GLP-1 drugs.
SLU-PP-332Preclinical: AnimalEndurance and exercise capacity. Unproven in people: sedentary mice injected twice daily for 7 days ran about 70% longer and 45% farther on a treadmill. Nothing has been measured in a person.
SLU-PP-332Preclinical: AnimalMuscle aging and inactivity. Unproven: in muscle cells from 10 inactive women, grown in a dish, it lowered oxidative stress and helped cells form muscle fibers. No one has taken it in a study.
MOTS-cPreclinical: AnimalExercise endurance. Unproven in people: young, middle-aged and old mice ran longer after injections; old mice ran about twice as long. In 10 young men, exercise itself raised muscle MOTS-c about 12-fold.
MOTS-cPreclinical: AnimalBone loss and osteoporosis. Unproven in people: it pushed rat bone-marrow stem cells toward bone-forming cells and limited bone loss around implant debris in mouse skulls. FDA found no human study for osteoporosis.
FOXO4-DRIPreclinical: AnimalFitness and frailty in old age. Unproven: in fast-aging mice and mice over 2 years old, it improved fitness, activity and kidney markers. Lifespan wasn’t measured, and nothing has been tested in people.
BPC-157Preclinical: AnimalTendon, ligament and muscle injuries. Unproven in people: rat studies report faster healing of injured tendons, ligaments and muscles. A 2025 systematic review found 36 orthopedic studies, 35 of them in animals or cells.
TB-500Preclinical: AnimalTendon and ligament injuries. Unproven in people: in a 2026 rat study, daily TB-500 for 4 weeks after Achilles tendon repair gave stronger, better-organized tendons. Adding BPC-157 added nothing.
CartalaxPreclinical: AnimalJoint and cartilage health (osteoarthritis). Unproven: in aging cartilage cells and human stem cells in a dish, it raised cartilage-building markers. A 2023 Russian review says oral use helped older people with osteoarthritis but cites no study.
MGFPreclinical: AnimalMuscle growth and strength. Unproven: no human study. A 2002 cell study saw muscle cells multiply, but two drug companies couldn’t repeat it in 2014. Mice engineered to make a related peptide gained muscle but lost strength.
MGFPreclinical: AnimalHealing muscle injuries. Unproven in people: injected into bruised mouse muscle, it reduced scarring and inflammation but didn’t speed the regrowth of muscle fibers (2019).
MGFPreclinical: AnimalTendon and bone repair. Unproven in people: a synthetic version improved healing of injured rat Achilles tendons (2016) and of bone gaps in rabbits (2011). Neither use has been tested in a person.
MGFPreclinical: AnimalSlowing age-related muscle loss. Unproven: a weight session raised muscle MGF in young adults but not in 70- to 82-year-olds. In a cell study, the peptide prolonged growth of muscle stem cells from young donors, not old ones.
AbaloparatideApproved drug: AnimalSpinal fusion surgery. Unproven in people: in rabbits, daily abaloparatide gave 100% fusion vs 45% with saline. A human trial in spinal fusion is still running, with results expected in 2027.
CJC-1295 with DACHuman studies: AnimalMuscle gain and fat loss. Unproven in people: no human study measured body composition. In growing mice lacking GHRH, daily shots for 5 weeks gave normal growth, lean mass and fat.
IpamorelinHuman studies: AnimalBone strength. Unproven in people: in rats it lengthened and enlarged bones, without making them denser, and offset steroid-driven losses of bone formation and muscle strength. No human bone study exists.
IGF-1 LR3Preclinical: AnimalMuscle growth. Unproven in people: in growing rats it raised weight gain and protein retention at a sixth of IGF-1’s dose, yet it didn’t protect muscle better in steroid-treated rats, and it slowed pig growth.
IGF-1 DESPreclinical: AnimalMuscle growth. Unproven in people: in rat muscle cells it was about 10 times as potent as IGF-1, and in steroid-treated rats about 2.5 times as potent at limiting weight and protein loss. Never tested in humans.
Follistatin-344Preclinical: AnimalMuscle growth in animals. In mice, follistatin made in muscle produced large muscle gains, more than blocking myostatin alone. Animal gains don’t show what injecting the protein would do in people.
ACE-031Human studies: AnimalMuscle wasting and frailty. Unproven in people beyond the single-dose trial. Related activin-receptor traps built muscle in animals, and no trial in muscle wasting or frailty was completed.
GHK-CuHuman studies: AnimalLung, gut and joint repair. Unproven in people: in mice it eased lung scarring and colitis, and in rats knee-ligament graft healing improved at 6 weeks but not at 12. None of these has been tested in humans.

Claims without data 23

Promoted by sellers, clinics or users, with no study behind the claim.

HGH Fragment 176-191Preclinical: No studyJoint, cartilage and muscle claims. Unproven: no study has tested this peptide for joints, cartilage or muscle in people or animals. The rabbit knee study often cited used AOD9604, a different peptide.
EcnoglutideApproved drug: No studyKnee osteoarthritis pain. Unproven: a 68-week phase 3 trial in 360 Chinese adults with obesity and knee osteoarthritis began recruiting in August 2026.
TB-500Preclinical: CommunityFaster recovery, less pain and stiffness. Unproven: users report easier movement and less pain within weeks. FDA’s 2026 review found no study that has given TB-500 to a person for any condition.
TB-500Preclinical: No studyMuscle growth, endurance and performance. Unproven: promoted online for muscle growth and stamina, with no study behind it. It’s banned in sport, and labs test athletes and racehorses for it.
CartalaxPreclinical: No studyBack, spine and bone health. Unproven: no published study has tested it on bones, spinal discs or back pain, in animals or people.
MGFPreclinical: No studyBodybuilding and faster recovery. Unproven: promoted online for muscle gain and recovery, with no human study behind it. It’s banned in sport at all times, and doping labs have found altered versions in seized vials.
PEG-MGFPreclinical: No studyMuscle growth and strength. Unproven: no study has tested PEG-MGF in people, animals or cells. The claims borrow from plain MGF, whose effect on muscle cells two drug companies couldn’t reproduce.
PEG-MGFPreclinical: No studyFaster recovery after training. Unproven: promoted for whole-body recovery from a few injections a week. A 2026 review found no human study of PEG-MGF; the protocols come from bodybuilding forums.
PEG-MGFPreclinical: No studyHealing injuries, heart and brain. Unproven: the tendon, bone, heart and brain studies in animals used the plain, unpegylated MGF peptide, a different molecule. None tested PEG-MGF.
PEG-MGFPreclinical: No studySlowing age-related muscle loss. Unproven: no study has given PEG-MGF to anyone. In a cell study, plain MGF prolonged growth of muscle stem cells from young donors, but not old ones.
ChonlutenPreclinical: No studyJoint and cartilage health. Some sellers market it for joints, apparently confusing it with cartilage peptides such as Cartalax; no study links it to joints.
CJC-1295 (no DAC)Preclinical: CommunityMuscle gain and fat loss. Unproven: widely marketed for building muscle and losing fat, but no study of this exact peptide has measured body composition, in people or in animals.
IpamorelinHuman studies: CommunityMuscle, fat loss and anti-aging. Unproven: widely marketed for muscle, fat loss, energy, skin and joints, but no human study has tested any of these, and none has given it under the skin.
TesamorelinApproved drug: CommunityMuscle gain and anti-aging. Unproven: no completed trial has tested it for building muscle or slowing aging. In the HIV trials, lean body mass rose 1.2–1.3 kg vs little change on placebo; a trial adding exercise is under way.
IGF-1 LR3Preclinical: CommunityTargeting one muscle by local injection. Unproven: no study has tested whether injecting it into one muscle helps that muscle. Injected into rat muscle, it entered the bloodstream and was undetectable after about 4 hours.
GHRP-2Approved drug: CommunityMuscle, fat loss and anti-aging. Unproven: no study has measured muscle, fat or aging outcomes. Five days of daily injections in 9 young men didn’t raise IGF-1; a 30-day infusion in 17 older adults did.
GHRP-6Human studies: CommunityMuscle growth and recovery. Unproven: no study has tested repeated doses or measured muscle. A 24-hour infusion raised IGF-1 12–22% in 8 young men, but blunted the response to a later dose.
IGF-1 DESPreclinical: CommunityLocal muscle growth by site injection. Unproven: the claim that its short life keeps it near the injection site hasn’t been tested. Injected into rat muscle, it reached the bloodstream and stayed detectable there for 24 hours.
Follistatin-344Preclinical: No studyInjecting follistatin protein for muscle. No published study has given follistatin protein to a person, so the dose, the effect and the safety of what people inject are untested.
MacimorelinApproved drug: No studyMuscle building or anti-aging. Unproven: no study has tested it for muscle, fat loss or aging. It is approved only as a single test dose, and WADA bans it at all times.
ACE-031Human studies: No studyStrength and athletic performance. No study has measured strength, power or performance. It is banned in sport at all times, and most products sold as ACE-031 are a different protein.
PalopegteriparatideApproved drug: No studyOsteoporosis or building bone. Not a use: it gives steady all-day PTH rather than daily pulses. In trials, high starting bone density fell toward normal, and in rats some doses caused net bone loss.
CosyntropinApproved drug: No studyAthletic performance or recovery. Unproven: no study shows a performance benefit, and corticotrophins, including tetracosactide by name, are banned in sport at all times (WADA S2.2.2).

Skin, hair and wounds 73

In more detail: peptides for hair loss.

In more detail: peptides for skin.

On a label 6

Approved uses, from a product label somewhere in the world.

Melanotan 1Approved drug: LabelErythropoietic protoporphyria (EPP). Scenesse implant is approved for adults with EPP, a rare disorder that makes light painful. Over 180 days, median pain-free hours in direct sun: 64.1 vs 40.5 on placebo implants.
PT-141Approved drug: LabelTanning or darker skin. Not a tanning agent: it can cause uneven dark patches on the face, gums or breasts (1% at up to 8 doses a month, 38% after 8 daily doses) that may not fade.
IcotrokinraApproved drug: LabelPlaque psoriasis. Approved in 2026 (US, Japan, EU) for moderate-to-severe plaque psoriasis. In ICONIC-LEAD (684 people), 65% vs 8% on placebo had clear or almost clear skin at week 16.
IcotrokinraApproved drug: LabelPsoriasis of the scalp, genitals, hands, feet. Covered by the approval. In ICONIC-TOTAL (311 people), the scalp cleared or nearly cleared in 65.9% vs 10.6% and the genitals in 76.5% vs 21.4%; hands and feet didn’t differ significantly.
IcotrokinraApproved drug: LabelCompared with deucravacitinib, another psoriasis pill. In two trials of 1,505 adults, more reached PASI 90 at week 24 on icotrokinra (65–66%) than on deucravacitinib (41–44%).
IcotrokinraApproved drug: LabelPustular or erythrodermic psoriasis. Approved in Japan only (September 2026) for these rare severe forms when other treatments fall short, after a small Japanese study of 19 people; not part of the US or EU approval.

Tested in people 30

Studied in people, whatever the result: some worked, many didn’t or are unproven.

TirzepatideApproved drug: TrialPsoriasis and psoriatic arthritis, with ixekizumab. Positive, not an approved use: in open-label trials in adults with overweight or obesity, adding tirzepatide to ixekizumab (Taltz) cleared psoriasis completely in 40.6% vs 29.0% at 36 weeks (274 people). In psoriatic arthritis, 33.5% vs 20.4% improved by at least half (271 people).
LiraglutideApproved drug: TrialPsoriasis. Mixed: in 20 people with overweight and normal blood sugar, 8 weeks didn’t improve psoriasis more than placebo. In 25 people with type 2 diabetes, psoriasis scores improved more over 12 weeks than in a control group.
GlutathioneApproved drug: TrialSkin lightening. Unproven by injection: the only placebo-controlled IV trial found 37.5% vs 18.7% improved, which could be chance. Oral and topical forms lightened skin modestly in small trials; a 2025 review advises against IV use.
Thymosin Beta-4Human studies: TrialLeg and pressure ulcers. Not shown: in Phase 2 gel trials, ulcers closed within 84 days in 12 of 55 (leg) and 8 of 54 (pressure) on the gel, vs 4 of 17 and 3 of 18 on placebo.
Thymosin Beta-4Human studies: TrialSkin blistering disease (epidermolysis bullosa). Not shown: in a 30-person gel trial stopped early, wounds had healed by day 56 in 8 of 22 people on the gel vs 5 of 8 on placebo.
GHK-CuHuman studies: TrialWrinkles and aging skin (creams, serums). Unproven: studies are small and short, and some were never fully published. A face cream improved wrinkles in 71 women over 12 weeks (poster only); an 8-week serum cut wrinkle volume 55.8% vs plain serum.
GHK-CuHuman studies: TrialChronic wounds and ulcers (gels, creams). Mixed: in a 1994 diabetic foot-ulcer trial, median closure was 98.5% vs 60.8% on plain gel; in a 1992 trial of 86 people with leg vein ulcers, a 0.4% cream matched placebo.
GHK-CuHuman studies: TrialHealing after laser resurfacing. Negative on objective measures: in 13 people after CO2 laser treatment, GHK-Cu skin care didn’t clear redness faster or improve wrinkles more than skin care without it, though patients rated their skin better.
GHK-CuHuman studies: TrialHair growth and thinning hair. Unproven: in a 2026 split-face study (18 people, 12 weeks), a 2% serum beat plain serum on eyebrow hair count. Scalp trials used mixes; a copper-free GHK complex raised hair counts in 45 men.
SNAP-8Human studies: TrialExpression lines and wrinkles. Unproven alone: two microneedle-patch studies run with patch makers mixed it with other actives; one (24 people, 28 days) beat a plain patch. The maker reports up to 62% (average 35%) wrinkle reduction, unpublished.
Melanotan 1Approved drug: TrialSunless tanning. Darkens skin, but no tanning product is approved: in a 28-man placebo-controlled trial (1991), 10 injections over 12 days darkened skin, peaking 1–3 weeks later. Long-term safety for tanning is unstudied.
Melanotan 1Approved drug: TrialVitiligo. Unproven: added to UV light therapy in a 55-person trial, implants gave 48.6% vs 33.3% repigmentation at day 168, mainly in darker skin types. A Phase 3 trial is under way.
Melanotan 1Approved drug: TrialAcne. Unproven: in a 3-person pilot, acne lesions fell within 56 days of one implant. No controlled trial has been published.
Melanotan 2Human studies: TrialSunless tanning. Tiny pilot, never approved: in the only tanning study (1996), 2 of 3 men had darker skin on the face, upper body and buttocks after 2 weeks of injections. No tanning product is approved.
ArgirelineHuman studies: TrialWrinkles around the eyes (creams). Mixed: in 60 Chinese adults, 4 weeks of cream improved eye wrinkles in 48.9% vs 0% on placebo, but a 19-woman split-face study found no difference. Other cream trials had 10–24 people.
ArgirelineHuman studies: TrialA “Botox in a jar” alternative. Not shown: in lab tests it acted far more weakly than botulinum toxin, and almost none passed the skin’s outer layer. With toxin shots for eyelid spasm (24 people), it didn’t significantly prolong their effect.
ArgirelineHuman studies: TrialOily skin and shine. Unproven: in a 4-week split-face trial in 14 people, a 10% lotion trended toward 10% less sebum than plain lotion, a difference that could have been chance (p = 0.16).
MatrixylHuman studies: TrialFine lines and wrinkles (creams). Limited: in a 12-week industry trial, 93 women saw more fine-line improvement on the side with 3 ppm than on the plain side; effect sizes weren’t given. A small 21-woman trial also favored it.
MatrixylHuman studies: TrialAnti-aging regimens with other actives. In an 8-week industry trial of 196 women, a regimen of niacinamide, peptides including this one and retinyl propionate improved wrinkles more than 0.02% tretinoin; its own share is unknown.
Palmitoyl tripeptide-1Human studies: TrialFine lines and wrinkles. Limited: the developer’s 4-week tests (23 and 15 women) reported slightly thicker skin and shallower wrinkles. Independent trials tested only mixes; the largest (60 people, 6 months) wasn’t significant vs vehicle.
Palmitoyl tripeptide-1Human studies: TrialRecovery after laser or microneedling. Mixed: in two split-face trials (26 and 25 adults), a serum pairing it with another peptide didn’t beat a moisturizer on redness, the main outcome; some secondary measures favored it.
Palmitoyl tripeptide-1Human studies: TrialFacial skin changes on GLP-1 drugs. Unproven: a 7-woman split-face pilot of a multi-ingredient serum containing it reported better skin quality and no side effects; its own share is unknown.
Syn-AkeHuman studies: TrialExpression lines and wrinkles. Unproven alone: in the maker’s unpublished 28-day test (45 volunteers), roughness fell 21% and wrinkle depth 20% (top single result 52%); industry studies tested only serums mixing it with other actives.
LeuphasylHuman studies: TrialExpression lines and wrinkles. Unproven alone: in the maker’s unpublished 28-day test (14 people, about 25 ppm), crow’s-feet wrinkles were 11.6% shallower on average; a 20-person study without a control group reported larger drops.
LeuphasylHuman studies: TrialBoosting Argireline in combined serums. Maker’s data only: wrinkles fell 24.6% with both peptides vs 16.3% with Argireline and 11.6% with Leuphasyl alone (14–15 people each, 28 days); no statistics were published.
LeuphasylHuman studies: TrialExtending botulinum toxin results. Unconfirmed: a trade-magazine report of 22 women using a peptide cream including it after toxin injections claimed a longer effect; it isn’t peer-reviewed.
Syn-CollHuman studies: TrialFine lines and wrinkles. Unproven alone: the maker reports a dose-related effect at 10–25 ppm and an 84-day study in 60 volunteers that beat placebo, summarized in reviews but never published in full.
Syn-CollHuman studies: TrialMicroneedle patches with other peptides. Mixed product only: in a 12-week single-center study, a patch with SNAP-8, adenosine and seaweed extract cut fine lines 25.8% from baseline, with no control group.
LL-37Human studies: TrialHealing venous leg ulcers. Not shown: in a 34-person trial, the weakest strength sped healing about sixfold vs placebo over 4 weeks, but a 148-person follow-up found no benefit overall after 13 weeks.
LL-37Human studies: TrialDiabetic foot ulcers. Unproven: in a 25-person trial, a cream applied twice weekly for 4 weeks built up more healthy new wound tissue than placebo, but didn’t cut bacteria or inflammation markers more.

Seen only in animals 20

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

FOXO4-DRIPreclinical: AnimalHair regrowth. Unproven: thinning fur grew denser in fast-aging and very old mice, a finding the 2017 authors weren’t looking for. No human study exists.
CardiogenPreclinical: AnimalTissue repair. Unproven: in mouse fibroblast cultures it raised structural proteins (actin, tubulin, vimentin, lamins) 2–5-fold, which its developers link to repair. Not tested in living animals or people.
TB-500Preclinical: AnimalWound and skin healing. Unproven: the non-acetylated peptide sped wound closure in aged mice (2003), but TB-500 itself didn’t close scratch wounds in a 2024 lab test, while one of its breakdown products did.
KPVPreclinical: AnimalSkin inflammation and wound healing. Unproven in people: it eased ear swelling in mice and sped corneal healing in rabbits. FDA reviewed it for these uses in 2026 and found no human data.
ARA-290Human studies: AnimalWound healing and tissue repair. Unproven in people: it sped wound healing in mice with diabetes. No human trial has tested it for wounds, and it isn’t sold as a repair peptide by approved routes.
CartalaxPreclinical: AnimalSkin aging and collagen. Unproven in people: in aging skin cells in a dish, it raised collagen I and sirtuins, proteins linked to cell aging, and curbed cell-death signals.
Thymosin Beta-4Human studies: AnimalHair growth. Unproven in people: it sped hair growth in rats and mice (2004). No controlled human study has tested it for hair loss.
GHRP-6Human studies: AnimalWound healing and scarring. Unproven in people: a GHRP-6 gel sped healing of skin wounds in rats and reduced raised scars in rabbits. It hasn’t been tested on human skin.
AHK-CuPreclinical: AnimalHair growth and hair loss. Unproven: the only study used donated human hair follicles and follicle cells in the lab (2007), where tiny amounts lengthened follicles and boosted cell growth. It hasn’t been tested on a living scalp.
SNAP-8Human studies: AnimalA “Botox-like” wrinkle relaxer. Unproven: in the maker’s lab tests, summarized in a 2020 review, it cut release of a nerve signaling chemical by 43% at high concentration. No study shows it relaxes muscles or reaches nerves through skin.
ArgirelineHuman studies: AnimalCollagen and skin thickening. Unproven in people: in aged mice, a 10% cream for 6 weeks thickened skin and raised type I collagen. A safety panel said it’s unclear whether such effects come from collagen or simple hydration.
MatrixylHuman studies: AnimalBoosting collagen. Unproven in people: its peptide raised collagen and fibronectin in cell studies, and in mouse skin a little reached the deeper layer. Whether it raises collagen in human skin hasn’t been shown.
MatrixylHuman studies: AnimalWound healing and scars. Unproven in people: in a 21-day animal study, patches and creams with it sped wound healing compared with no treatment. No human wound or scar trial exists.
Palmitoyl tripeptide-1Human studies: AnimalBoosting collagen. Unproven in people: it raised collagen in cell and donated-skin tests, but in volunteers it stayed in the dead outer skin layer. No study shows more collagen in living skin.
Palmitoyl tripeptide-1Human studies: AnimalHair loss. Unproven: a 2026 mouse study of a mix with EGCG and biotin reported hair regrowth; no human hair study of it exists.
Syn-AkeHuman studies: AnimalA “Botox-like” or “snake venom” wrinkle relaxer. Unproven: it mimics a viper-venom toxin, and in the maker’s lab tests it cut contractions of nerve-connected muscle cells by 82%. No study shows it relaxes facial muscles through skin.
LeuphasylHuman studies: AnimalA “Botox-like” wrinkle relaxer. Unproven: it’s an enkephalin-like peptide that binds opioid receptors in lab tests, and its maker reports less nerve-signal release from cultured neurons. No study shows it reaches nerves through skin.
Syn-CollHuman studies: AnimalFirmer skin and collagen boosting. Unproven in people: in the maker’s lab tests it raised collagen through TGF-beta and curbed collagen-breaking enzymes. No study shows more collagen in living skin.
LL-37Human studies: AnimalSkin conditions such as rosacea or psoriasis. Evidence points the other way: people with rosacea have abnormally high levels in facial skin, injecting these peptides inflamed mouse skin, and lab studies tie LL-37 to psoriasis inflammation.
VilonPreclinical: AnimalSkin aging. Unproven: in aging human skin cells grown in a dish it lowered inflammatory signals and raised sirtuin-6, a protein linked to DNA repair. Not tested on skin in people.

Claims without data 17

Promoted by sellers, clinics or users, with no study behind the claim.

SetmelanotideApproved drug: No studyTanning. Not a use: skin darkening, from its action on pigment-cell (MC1) receptors, is a side effect in most users, and no study has tested it for tanning.
EpithalonPreclinical: No studySkin and youthful appearance. Unproven: promoted online for skin health and reversing signs of aging, FDA notes, but no published human study has tested it on skin.
FOXO4-DRIPreclinical: No studySkin rejuvenation. Unproven: no study has tested it on skin aging. The only skin work used keloid scar tissue in the lab, where it killed senescent scar cells.
TB-500Preclinical: No studyHair growth. Unproven: FDA found TB-500 promoted for hair growth, but the hair studies used full-length thymosin beta-4 in rats and mice. No study has tested TB-500 itself.
KPVPreclinical: No studyPsoriasis and eczema. Unproven: FDA evaluated KPV for inflammatory conditions including psoriasis and eczema and found no human studies; approved treatments exist for both.
GHK-CuHuman studies: CommunityInjections for skin, healing or anti-aging. Unproven: no study has tested GHK-Cu injections alone in people. FDA found limited human data on their safety, and the nomination to compound injectable GHK-Cu was withdrawn in April 2026.
AHK-CuPreclinical: CommunityInjections for hair or skin. Unproven: some users report injecting it, but no study has tested AHK-Cu by injection in people or animals, and cosmetic serums aren’t sterile.
AHK-CuPreclinical: No studySkin firming, collagen and anti-aging. Unproven: no study of AHK-Cu on skin was found. These claims borrow from GHK-Cu, a related copper peptide whose own human evidence is small and mixed.
SNAP-8Human studies: No studyInjections for wrinkles. Unproven: no study has tested SNAP-8 by injection in people or animals, and cosmetic-grade peptide isn’t made to injectable standards.
Melanotan 2Human studies: No studyProtection from sun damage. Unproven, and case reports point the other way: no study has measured sun protection, while several describe melanomas arising in moles during or after melanotan use.
ArgirelineHuman studies: CommunityInjections or threads for wrinkles. Unproven: no trial has tested injected Argireline, and a woman given forehead and temple injections developed a hard-to-treat mycobacterial skin infection that took 5 months of antibiotics to clear.
MatrixylHuman studies: No studyInjections or mesotherapy. Unproven: no study has tested Matrixyl by injection in people or animals, and cosmetic-grade peptide isn’t made to injectable standards.
Palmitoyl tripeptide-1Human studies: No studyInjections or mesotherapy. Unproven: no study has tested palmitoyl tripeptide-1 by injection in people or animals, and cosmetic-grade peptide isn’t made to injectable standards.
Syn-AkeHuman studies: CommunityAlongside botulinum toxin injections. Untested: clinicians in an industry-supported case report pair a serum containing it with toxin injections; no controlled study has measured any added benefit.
Syn-AkeHuman studies: No studyInjections for wrinkles. Unproven: no study has tested Syn-Ake by injection in people or animals, and cosmetic-grade peptide isn’t made to injectable standards.
LeuphasylHuman studies: No studyInjections for wrinkles. Unproven: no study has tested Leuphasyl by injection in people, and cosmetic-grade peptide isn’t made to injectable standards.
Syn-CollHuman studies: No studyInjections or mesotherapy. Unproven: no study has tested Syn-Coll by injection in people or animals, and cosmetic-grade peptide isn’t made to injectable standards.

Brain, mood and nerves 89

In more detail: peptides for anxiety and focus.

On a label 12

Approved uses, from a product label somewhere in the world.

CosyntropinApproved drug: LabelMultiple sclerosis flare-ups. Licensed in Australia as Synacthen Depot for acute relapses of multiple sclerosis. Not an approved use of cosyntropin in the US or UK.
SelankApproved drug: LabelAnxiety and stress disorders. Registered in Russia as nonprescription nose drops for adults with anxiety states and stress disorders. In a 62-person trial, anxiety eased about as much as on medazepam, a benzodiazepine; there was no placebo group.
SemaxApproved drug: LabelStroke treatment and recovery. Registered in Russia: 1% drops as add-on care in acute ischemic stroke, 0.1% drops for recovery. In a 1997 study, 30 patients on Semax regained function faster than 80 on usual care; no randomization described.
SemaxApproved drug: LabelThinking problems from poor brain blood flow. The 0.1% drops are registered in Russia for memory and thinking problems from brain blood-vessel disease. A 187-person Russian study reported fewer strokes, without figures; FDA’s 2026 review found the evidence insufficient.
CerebrolysinApproved drug: LabelStroke recovery. Licensed in several EU countries and Russia. CASTA (1,070 people) missed its 90-day goal and a 2023 Cochrane review found no effect on deaths; a 208-person rehab trial reported better arm function.
CerebrolysinApproved drug: LabelAlzheimer’s disease. Licensed in Croatia (as add-on care for mild to moderate disease) and Russia. Pooling 6 placebo trials, a thinking-score gain at 4 weeks wasn’t significant by 6 months; global ratings favored it.
CerebrolysinApproved drug: LabelTraumatic brain injury. Licensed in Croatia, as add-on care, and in Russia. In CAPTAIN II (139 analyzed), a combined 13-scale outcome favored it at day 90; CAPTAIN I (46 people) narrowly missed its main goal.
ZiconotideApproved drug: LabelSevere chronic pain needing a spinal pump. Approved for adults who need intrathecal treatment and don’t tolerate or respond to other options. In the slow-titration trial of 220 adults, pain improved 14.7% vs 7.2% on placebo over 3 weeks.
CortexinApproved drug: LabelIschemic stroke recovery. Registered in Russia for stroke. In a 272-person placebo-controlled trial, results were shown only in graphs, with 7 deaths on Cortexin vs none on placebo; a Cochrane review found no clear benefit.
CortexinApproved drug: LabelMemory and thinking problems (cognitive impairment). Registered in Russia for cognitive impairment. A 189-person randomized Russian study without placebo reported dose-dependent benefits in chronic brain ischemia; its abstract gives no numbers.
CortexinApproved drug: LabelTraumatic brain injury and its after-effects. Registered in Russia for brain injury and its after-effects. No placebo-controlled trial in brain injury was found in PubMed; Russian reviews describe benefit without trial numbers.
CortexinApproved drug: LabelEncephalopathy, encephalitis and epilepsy. Registered in Russia as an add-on for these. Supporting studies are small and Russian, most without placebo; one uncontrolled 40-person study reported better test scores in alcohol-related brain damage.

Tested in people 46

Studied in people, whatever the result: some worked, many didn’t or are unproven.

SemaglutideApproved drug: TrialSlowing Alzheimer’s disease. Negative: in two 2-year trials of 3,808 people with early Alzheimer’s, daily semaglutide tablets didn’t slow decline compared with placebo.
AOD9604Human studies: TrialNerve pain, migraine and sciatica. Not shown: tested under the code LAT8881 in three small placebo-controlled trials (about 100 people, 2019–2023), single IV or oral doses and 4 weeks of capsules didn’t relieve pain significantly.
L-CarnitineApproved drug: TrialFatigue in multiple sclerosis. Unproven: in an open study, oral L-carnitine (3–6 g a day) eased fatigue in 63% of people with multiple sclerosis who had low carnitine levels and fatigue on their MS drugs. There was no placebo group.
LiraglutideApproved drug: TrialSlowing Alzheimer’s disease. Not shown: in a 52-week trial of 204 people with mild to moderate Alzheimer’s, liraglutide didn’t change brain sugar use, the main measure, or daily function; one thinking score improved.
ExenatideApproved drug: TrialParkinson’s disease. Negative: in a 96-week phase 3 trial of 194 people, weekly exenatide didn’t slow worsening of movement symptoms vs placebo; a smaller 2017 trial had hinted at benefit.
ExenatideApproved drug: TrialAlzheimer’s disease and memory. Not shown: weekly exenatide didn’t improve thinking scores in 32 people with mild memory problems over 32 weeks, and a small Alzheimer’s trial, stopped early, found no clinical benefit.
ExenatideApproved drug: TrialHigh brain fluid pressure (IIH). Early signal: in a 12-week trial of 16 women with idiopathic intracranial hypertension, exenatide lowered pressure inside the skull more than placebo. Larger trials are needed.
TesofensineHuman studies: TrialParkinson’s disease. Not shown: in 261 people with early Parkinson’s, 14 weeks brought no significant benefit; in advanced disease, small gains at two doses lacked a dose response.
TesofensineHuman studies: TrialAlzheimer’s disease. Negative: a 14-week trial in 430 people with mild to moderate Alzheimer’s didn’t show benefit; the drug was later repurposed for obesity.
DulaglutideApproved drug: TrialSlowing memory and thinking decline. Unproven: in an exploratory REWIND analysis of 8,828 people over 5.4 years, the main result wasn’t significant; after adjusting for baseline scores, substantial decline was 14% less likely.
LixisenatideApproved drug: TrialParkinson’s disease. Promising, unconfirmed: in a 12-month phase 2 trial of 156 people with early Parkinson’s, motor scores held steady vs a 3-point worsening on placebo; 46% had nausea. A larger exenatide trial was negative.
NAD+Human studies: TrialParkinson’s disease. Not shown: an uncontrolled report of 885 patients given IV or oral NADH claimed improvement, but a small double-blind trial of IV and muscle NADH injections found no significant benefit.
NAD+Human studies: TrialMemory and dementia. Not shown: in a 3-month open study, oral NADH didn’t improve memory or thinking tests in 19 people with dementia. Injected NAD+ hasn’t been tested.
GlutathioneApproved drug: TrialParkinson’s disease. Not shown: IV glutathione 3 times a week for 4 weeks (21 people) and a nasal spray for 3 months (45 people) did no better than placebo.
VesugenPreclinical: TrialWork stress in truck drivers. Unproven: a Russian study of truck drivers reported better stress and mood scores, best with Vesugen plus Pinealon. The abstract doesn’t say how many took them, at what dose, or against what comparison.
CarnosineHuman studies: TrialMemory and thinking. Unproven: no cognitive benefit in a 49-person diabetes trial, and only some executive-function measures improved in 75 adults with schizophrenia. Memory gains in older adults came from anserine–carnosine mixes.
CarnosineHuman studies: TrialDepression and OCD, added to antidepressants. Small positive trials: added to citalopram (58 adults, 6 weeks) or fluvoxamine (44 adults, 10 weeks), symptom scores fell more than with placebo. Both come from one Tehran research group and haven’t been replicated.
ARA-290Human studies: TrialNerve pain in sarcoidosis. Promising but unfinished: in three Phase 2 trials (22–64 people, 28 days) symptom scores beat placebo, and at 4 mg small corneal nerve fibers grew. No Phase 3 trial has run.
ARA-290Human studies: TrialPainful nerve damage in type 2 diabetes. Positive in one small trial: 48 adults on 4 mg daily for 28 days improved 3.3 points on a nerve-pain questionnaire vs 1.1 on placebo, with gains holding a month later.
ARA-290Human studies: TrialLow mood and depression. Not shown: in 36 healthy volunteers, a single 2 mg IV dose didn’t shift emotional processing toward the positive a week later, the pattern antidepressants produce.
CalcitoninApproved drug: TrialSpinal stenosis leg pain. Negative: in 40 people with lumbar spinal stenosis, 4 weeks of nasal calcitonin didn’t improve disability, leg pain or walking distance more than placebo.
CalcitoninApproved drug: TrialPhantom limb pain. Unproven: IV infusions eased early phantom pain after amputation in a 21-person crossover trial (1992), but a 2008 trial found no benefit for long-standing phantom pain.
TesamorelinApproved drug: TrialMemory and thinking in aging. Unproven: in a 20-week trial of 152 adults aged 55–87, planning and attention tests (executive function) improved vs placebo. A 10-week pilot (22 adults) and a 6-month HIV trial (73) found no clear benefit.
MK-677Human studies: TrialSlowing Alzheimer’s disease. Negative: in 563 people with mild to moderate Alzheimer’s, a year of daily MK-677 raised IGF-1 73% but didn’t slow decline compared with placebo.
MecaserminApproved drug: TrialALS (motor neuron disease). Negative: a 2-year trial in 330 adults found no benefit. Earlier 9-month trials disagreed: 26% slower decline in one of 266 people, no difference in one of 183.
OxytocinApproved drug: TrialTrust and bonding (the “love hormone”). Unproven: early lab studies suggested a single nasal dose raised trust, but a large registered replication (2020) found no effect. Most studies tested single doses in healthy volunteers.
GonadorelinApproved drug: TrialCognition in Down syndrome. Unproven: a small pilot reported better cognition and brain connectivity in adults with Down syndrome on pump therapy. A placebo-controlled trial is under way.
CosyntropinApproved drug: TrialHeadache after spinal or epidural puncture. Mixed: one 1 mg IV dose cut headaches after accidental dural puncture to 33% from 69% in a 90-woman trial (2010), but a 2025 trial found no benefit for established headaches.
SelankApproved drug: TrialAdd-on to benzodiazepine treatment. Unproven: in 70 patients with anxiety disorders, adding Selank to phenazepam brought a faster response and fewer phenazepam side effects, such as sedation, than phenazepam alone. No placebo group; few numbers reported.
SelankApproved drug: TrialFocus, memory and learning. Unproven: the Russian label claims better memory and attention, and one 60-person anxiety trial reported a mild boost to thinking, without figures. No study has measured thinking in healthy people.
SemaxApproved drug: TrialFocus and memory in healthy people. Unproven: its developers’ 1997 review says it improved memory and attention in healthy men under extreme working conditions, without details. Small brain-scan studies of single doses measured brain activity, not thinking.
SemaxApproved drug: TrialMigraine and nerve pain. Not shown: in a small uncontrolled study, one nasal dose ended headache in 4 of 12 people with migraine and didn’t help typical trigeminal neuralgia (facial nerve pain), per FDA’s 2026 review.
DSIPApproved drug: TrialChronic pain and migraine. Unproven: in a 7-person pilot without a control group, IV DSIP lowered pain in 6 people with migraine, other headaches, tinnitus or psychogenic pain attacks (1984).
CerebrolysinApproved drug: TrialVascular dementia. Unproven: a 2019 Cochrane review of 6 trials (597 people) found small gains in thinking and overall function but called the evidence very low quality; benefits may be too small to matter.
CerebrolysinApproved drug: TrialMemory and focus in healthy people. Unproven: in 48 healthy men, 10 days of infusions changed brain waves but not clearly memory; a single oral dose study in older adults, without a placebo group, reported fewer memory errors.
CerebrolysinApproved drug: TrialMultiple sclerosis relapse recovery. Not shown: in a 40-person Russian trial after steroid treatment for a relapse, 10 daily IV infusions didn’t improve disability scores more than saline, though two tests of thinking and function improved more.
PinealonPreclinical: TrialMemory after brain injury. Unproven: its developers’ 2020 review says capsules plus standard care improved memory and headaches in 72 people with brain-injury after-effects; the study itself, with its design and numbers, couldn’t be found.
PinealonPreclinical: TrialStress and work fatigue. Unproven: a Russian study of truck drivers reported better stress and mood scores, best with pinealon plus vesugen, a related peptide. The abstract doesn’t say how many took them, at what dose, or against what comparison.
DihexaHuman studies: TrialAlzheimer’s disease, via its prodrug. Not shown: in LIFT-AD, 26 weeks of the injected prodrug fosgonimeton didn’t improve thinking or daily function vs placebo in 287 people with mild to moderate Alzheimer’s.
DihexaHuman studies: TrialParkinson’s or Lewy body dementia, via prodrug. Unproven: the prodrug’s phase 2 SHAPE trial stopped early after enrolling 28 people, citing design limitations; the registry reports no efficacy results.
ZiconotideApproved drug: TrialCancer or AIDS pain. In a 111-person trial with fast dose increases over 5–6 days, pain scores improved 53.1% vs 18.1% on placebo; side effects were frequent at those doses.
ZiconotideApproved drug: TrialChronic non-cancer pain. In 255 adults, pain fell 31.2% vs 6.0% on placebo over 6 days of fast titration, but dizziness, nausea and gait problems were common; the label now uses slower increases.
ZiconotideApproved drug: TrialNerve pain after spinal cord injury. Unproven: in a French series, 14 of 20 people had 40%+ less pain on a test dose, and 8 of 11 given pumps kept the benefit for about 3.6 years. No controlled results yet.
ZiconotideApproved drug: TrialPain after surgery. Pilot only: in 30 surgical patients, a 2–3 day intrathecal infusion lowered morphine use at 24–48 hours, but the higher dose caused dizziness, blurred vision and sedation. Not an approved use.
CortexinApproved drug: TrialFatigue and brain fog after COVID-19. Unproven: a 979-person Russian observational program reported less fatigue and better test scores after 10-day courses, but it had no control group.
ThymulinHuman studies: TrialMultiple sclerosis. No benefit: in 40 matched patients injected for 6 months, disability, walking and function were no different from placebo.

Seen only in animals 23

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

MazdutideApproved drug: AnimalMemory and thinking in diabetes. Unproven in people: in diabetic mice it improved memory-test performance more than dulaglutide. A trial in 420 people with type 2 diabetes and early cognitive decline is recruiting.
HumaninPreclinical: AnimalAlzheimer’s disease and memory. Unproven in people: it protected nerve cells from Alzheimer’s-linked damage in culture and improved learning tests in old mice. A gene variant that lowers humanin levels was linked with faster cognitive aging.
VesugenPreclinical: AnimalAlzheimer’s disease. Unproven in people: in a mouse model of Alzheimer’s, daily injections prevented loss of dendritic spines, the contact points between nerve cells; a gain in plasticity was only a trend.
BPC-157Preclinical: AnimalBrain and nerve protection. Unproven in people: rodent studies report protection in models of stroke, brain damage and spinal cord injury. It has never been tested for these in humans.
MGFPreclinical: AnimalBrain and nerve protection. Unproven in people: it protected brain cells in gerbils after blood flow to the brain was briefly cut (2005), and dopamine nerve cells in a rat model of Parkinson’s disease (2009).
Thymosin Beta-4Human studies: AnimalStroke and brain injury recovery. Unproven in people: rat studies report better recovery of movement and learning after stroke and traumatic brain injury. It hasn’t been tested for these in humans.
IGF-1 DESPreclinical: AnimalBrain protection after injury. Not shown: in rats with oxygen-deprivation brain injury, IGF-1 delivered into the brain reduced nerve-cell loss, but des-IGF-1 didn’t at two doses; a higher dose showed only a trend.
SelankApproved drug: AnimalDepression and low mood. Unproven: the Russian label credits it with an antidepressant effect, and it reduced depression-like behavior in rats and mice. No trial has tested it in people with depression.
SemaxApproved drug: AnimalDepression and low mood. Unproven: daily injections eased depression-like behavior in stressed rats (2024). No adult trial has tested it for depression, and the Russian labels rule it out in anxiety disorders.
PinealonPreclinical: AnimalBrain protection after low oxygen or stroke. Unproven in people: in old rats it improved survival after blocked neck arteries and learning after low oxygen, but in one study it reduced movement and raised a cell-death enzyme.
PinealonPreclinical: AnimalAlzheimer’s disease. Unproven in people: in a mouse model of Alzheimer’s, injections restored dendritic spines, the contact points between nerve cells, to normal density. It hasn’t been tested in anyone with dementia.
DihexaHuman studies: AnimalMemory and learning. Unproven in people: oral dihexa improved maze learning in impaired rats (2013) and Alzheimer’s-model mice (2021). The main papers on how it works were retracted in 2025.
DihexaHuman studies: AnimalHuntington’s disease. Not shown: in a 2024 rat model of Huntington’s disease, dihexa didn’t protect against weight, movement or memory problems.
PE-22-28Preclinical: AnimalDepression. Unproven in people: in mice, 4 days of PE-22-28 reduced depression-like behavior and boosted new nerve cell growth (2017). It has never been tested in a person.
PE-22-28Preclinical: AnimalStroke recovery and post-stroke depression. Unproven in people: in a 2019 mouse stroke model, daily injections eased movement and memory deficits and prevented depression-like behavior.
CortagenPreclinical: AnimalNerve injury recovery. Unproven in people: in rats with a repaired sciatic nerve, 10 days of injections sped fiber regrowth by 27% and conduction by 40%. Developers report human benefit; no human study is published.
CortagenPreclinical: AnimalChronic poor blood flow to the brain. Unproven in people: in rats with chronic brain ischemia it sped recovery of normal behavior and limited oxidative damage, much like the brain extract Cortexin.
CortagenPreclinical: AnimalSlowing brain aging. Unproven: in tissue culture it stimulated growth of rat brain-cortex tissue and loosened tightly packed chromatin in white blood cells from people aged 75–88.
P21Preclinical: AnimalAlzheimer’s disease. Unproven in people: in Alzheimer’s-model mice, months of P21 in food reduced tau buildup, lowered soluble amyloid-β and improved memory. It has never been tested in anyone with Alzheimer’s.
P21Preclinical: AnimalMemory decline with aging. Unproven: in 22–24-month-old rats, P21 by mouth eased age-related learning and memory decline, restored new nerve-cell growth and lowered tau in spinal fluid. No human data.
P21Preclinical: AnimalMemory and focus in healthy adults. Unproven: healthy adult mice given P21 did better on learning and memory tests in its 2010 debut study. No study has tested it in healthy people.
P21Preclinical: AnimalDown syndrome. Unproven: given to pregnant and nursing mice of a Down syndrome model, it prevented developmental delay in the pups and memory problems in adulthood. Never tested in people.
ThymulinHuman studies: AnimalInflammation and nerve pain. Unproven in people: in rats, thymulin and a synthetic lookalike reduced inflammatory and nerve pain and damped inflammatory signaling in the spinal cord.

Claims without data 8

Promoted by sellers, clinics or users, with no study behind the claim.

OxytocinApproved drug: CommunityInjections for mood, libido or bonding. Unproven: no published study has tested under-the-skin injections for these. The approved injection’s known effects include uterine contractions and water retention.
AdamaxPreclinical: No studyFocus and memory. Unproven: sold for focus and memory, but Adamax has never been studied in animals or people. The claim is borrowed from Semax, whose own evidence is small Russian studies.
AdamaxPreclinical: No studyMood and stress. Unproven: no study has tested Adamax for mood, stress or anxiety. Semax’s Russian labels rule out its use in anxiety disorders.
AdamaxPreclinical: No studyBrain protection and BDNF. Unproven: the claim borrows rat findings for Semax, which raised BDNF, a nerve growth factor, in the brain. Nothing has been measured for Adamax.
DihexaHuman studies: CommunityFocus and productivity in healthy people. Unproven: users report sharper focus and vivid dreams, but no study has given dihexa to a person; FDA found no human exposure data by any route.
PE-22-28Preclinical: CommunityFocus, motivation and anxiety. Unproven: users describe lifted mood or drive, and some notice nothing. No study has tested it in people for mood, focus or anxiety.
CortagenPreclinical: No studyMemory, focus and mood. Unproven: no study has tested it for memory, focus or mood in people; guides extrapolate from rat and cell work.
CortexinApproved drug: No studyMemory boost in healthy people. Unproven: no controlled study has tested it for memory or focus in healthy adults. The label covers only people with brain disorders.

Sleep 19

In more detail: peptides for sleep.

On a label 1

Approved uses, from a product label somewhere in the world.

TirzepatideApproved drug: LabelObstructive sleep apnea. Zepbound is approved for moderate to severe sleep apnea with obesity. At 52 weeks, breathing pauses and dips fell by 25.3–29.3 an hour, from about 50, vs 5.3–5.5 on placebo.

Tested in people 10

Studied in people, whatever the result: some worked, many didn’t or are unproven.

RetatrutideHuman studies: TrialObstructive sleep apnea. Positive: among 243 TRIUMPH-1 adults with sleep apnea, breathing pauses and dips fell by 22.9–34.3 an hour vs 9.9 on placebo at 80 weeks.
LiraglutideApproved drug: TrialSleep apnea. Modest benefit, not approved: in a 32-week trial of 359 adults with obesity and moderate to severe sleep apnea, breathing pauses and dips fell by 12.2 an hour vs 6.1 on placebo, from about 49.
Maridebart cafraglutideHuman studies: TrialObstructive sleep apnea. Unproven: two phase 3 trials (MARITIME-OSA-1 and -2, about 250 adults each) are measuring breathing pauses during sleep at 52 weeks; main results are expected from late 2027.
AmycretinHuman studies: TrialObstructive sleep apnea. Unproven: AMAZE 3 and 4 (about 300 adults each) are testing weekly injections in sleep apnea with excess weight; main results are expected in mid-2028.
EpithalonPreclinical: TrialSleep and melatonin. Unproven: in 40 women on night shifts, a 20-day under-the-tongue spray raised a urine melatonin marker 1.7-fold vs no change on placebo, but sleep wasn’t measured. FDA found no evidence it treats insomnia.
GHRP-2Approved drug: TrialDeeper sleep. Not shown: in a sleep-lab study of 7 young men, a late-night IV dose didn’t increase deep sleep; there was a nonsignificant trend toward more time awake in the next hour.
GHRP-6Human studies: TrialDeeper sleep. Not shown: repeated IV doses at night added light (stage 2) sleep in healthy men but left deep sleep unchanged, and raised cortisol, a stress hormone.
HexarelinHuman studies: TrialDeeper sleep. Negative: in 7 young volunteers, four IV doses at night reduced deep sleep and raised cortisol and prolactin, unlike ghrelin, which deepens sleep.
MK-677Human studies: TrialBetter sleep. Small studies: bedtime doses for 1–2 weeks increased deep sleep about 50% and REM sleep more than 20% in 8 young adults, and REM sleep in 6 older adults.
DSIPApproved drug: TrialInsomnia and deeper sleep. Mixed: one researcher’s small IV trials reported better sleep, but two other placebo-controlled trials (16 and 6 insomniacs) found weak or no benefit. No controlled trial has tested nasal or under-the-skin doses.

Claims without data 8

Promoted by sellers, clinics or users, with no study behind the claim.

OrforglipronApproved drug: No studySleep apnea. Unproven so far: a 712-person trial in sleep apnea with obesity finished in July 2026, but no results have been posted or published.
EcnoglutideApproved drug: No studySleep apnea. Unproven: two phase 3 trials in Chinese adults with obesity and obstructive sleep apnea, 140 people each, began in 2026; no results yet.
EloralintideHuman studies: No studySleep apnea and knee osteoarthritis pain. Unproven: 64-week phase 3 trials in obstructive sleep apnea and in knee osteoarthritis pain began in February 2026, with results expected in 2028.
CJC-1295 (no DAC)Preclinical: CommunityBetter sleep and recovery. Unproven: users and clinic websites claim deeper sleep and faster recovery, usually from a bedtime shot mixed with ipamorelin. No study has tested either claim.
CJC-1295 with DACHuman studies: CommunitySleep, recovery and anti-aging. Unproven: commonly claimed by users and clinics, but no study has tested any of these. The human trials measured only hormone levels and side effects.
IpamorelinHuman studies: CommunityBetter sleep. Unproven: often taken at bedtime for deeper sleep, but no study has tested this. In the IV surgery trial, insomnia was more common on ipamorelin (10.7% vs 5.2%).
SermorelinHuman studies: CommunityBetter sleep. Unproven: clinics promote bedtime shots for deeper sleep, but no published trial has tested sermorelin injections for sleep. The former label set bedtime dosing for children’s growth, not for sleep.
PinealonPreclinical: No studySleep and melatonin. Unproven: despite the name, no published study has tested it for sleep or melatonin. Its developers describe it as derived from Cortexin, a calf brain-cortex extract, not the pineal gland.

Hormones, sex and reproduction 70

In more detail: peptides for men’s health.

In more detail: peptides for women’s health.

On a label 24

Approved uses, from a product label somewhere in the world.

CalcitoninApproved drug: LabelHigh blood calcium (hypercalcemia). Approved for early emergency treatment alongside other drugs. In 4 small trials (53 patients), calcium began falling within 1–2 hours and was about 9% lower 8 hours after a dose.
SermorelinHuman studies: LabelTesting pituitary growth hormone reserve. Approved in 1990 as a one-dose IV test, discontinued in 2008. A normal result can’t rule out deficiency arising in the hypothalamus (the brain area controlling the pituitary), so other tests were needed.
GHRP-2Approved drug: LabelDiagnosing growth hormone deficiency. Approved in Japan only as a one-time IV test. In the validation study, GH peaked at 84.6 mcg/L on average in 77 healthy adults vs 1.36 in 58 adults with severe deficiency.
Somatropin (HGH)Approved drug: LabelGrowth hormone deficiency in adults. Approved as replacement once testing confirms the deficiency. Across 54 trials in over 3,400 adults, body fat fell 2.6 kg and lean mass rose 1.4 kg vs placebo, with more swelling.
MacimorelinApproved drug: LabelDiagnosing growth hormone deficiency in adults. Approved as a one-time oral test. Against the insulin tolerance test in 140 adults, results agreed in 94% without the deficiency and 74% with it, without inducing low blood sugar.
OctreotideApproved drug: LabelAcromegaly. Approved when surgery, radiation and bromocriptine fall short. In a 6-month trial of 115 people, IGF-1 normalized in 55–68%; the monthly depot controlled GH and IGF-1 about as well as daily shots.
hCGApproved drug: LabelLow testosterone from a pituitary cause. Approved for selected men with hypogonadotropic hypogonadism. Gonadotropin treatment (hCG, often with FSH) started sperm production in 75% of men with none, in a 2014 meta-analysis of 44 studies.
hCGApproved drug: LabelTriggering ovulation and IVF. Approved to trigger ovulation in women without primary ovarian failure after follicle-stimulating drugs; recombinant hCG is approved as an IVF trigger. Risks include ovarian overstimulation and multiple births.
PT-141Approved drug: LabelLow sexual desire in premenopausal women. Vyleesi is approved for acquired, generalized low desire causing distress. In two 24-week trials, desire scores (range 1.2–6) rose 0.5–0.6 vs 0.2 on placebo; distress scores fell 0.7 vs 0.4.
PT-141Approved drug: LabelMore satisfying sex. Not shown: in the phase 3 trials, satisfying sexual events didn’t rise more than with placebo. An earlier 12-week trial found 0.7 vs 0.2 more a month on pooled higher doses.
OxytocinApproved drug: LabelStarting or strengthening labor. Pitocin is approved, by IV drip in hospital, for medically needed labor induction and weak labor. The label says data are too limited to support elective induction.
OxytocinApproved drug: LabelBleeding after childbirth. Approved to control bleeding after delivery. In a WHO trial of 29,645 women, 10 IU into muscle matched heat-stable carbetocin: 14.4% vs 14.5% lost 500 mL or more or needed more drugs.
GonadorelinApproved drug: LabelTesting pituitary function. Licensed in the UK as a single 100 mcg injection: LH measured over 2 hours shows whether the pituitary can still respond. The label says it doesn’t identify the cause of a poor response.
GonadorelinApproved drug: LabelOvulation in hypothalamic amenorrhea. Licensed in France (Lutrelef, by pump) when the brain makes too little GnRH. In a 25-year series of 66 women, ovulation occurred in 96% of cycles, with one twin pregnancy (1.6%).
TriptorelinApproved drug: LabelEndometriosis, fibroids and IVF. Licensed in the UK and Europe (Decapeptyl, Gonapeptyl) for endometriosis, for fibroids before surgery, and as daily injections that prevent premature ovulation during IVF. Not approved for these in the US.
TriptorelinApproved drug: LabelReducing sex drive in severe paraphilias. Salvacyl is licensed in the UK to lower testosterone reversibly to castrate levels, reducing sex drive in adult men with severe sexual deviations.
DesmopressinApproved drug: LabelCentral diabetes insipidus. Approved as tablets, oral solution, nasal spray and injection to replace the missing hormone. Tablets cut urine output for up to 8 hours at usual doses and 12 hours at higher ones.
PalopegteriparatideApproved drug: LabelHypoparathyroidism in adults. Approved for adults. At 26 weeks, 68.9% vs 4.8% on placebo had normal calcium without active vitamin D or high-dose calcium by FDA’s count (79% vs 5% in the published analysis).
CosyntropinApproved drug: LabelTesting for adrenal insufficiency. Approved in the US and abroad as a one-off test: cortisol is measured before and 30–60 minutes after an injection, and a level under 18 mcg/dL suggests the adrenal glands aren’t responding normally.
LeuprolideApproved drug: LabelEndometriosis. Lupron Depot is approved for pain and lesions, for up to 6 months alone or 12 with add-back hormone. In trials, pain relief matched danazol, and periods stopped in 98% by the second month.
LeuprolideApproved drug: LabelUterine fibroids with anemia before surgery. Approved with iron for up to 3 months: at 12 weeks, 75% reached normal hemoglobin and hematocrit vs 49% on iron alone. The uterus regrew to its old size in about 8 months.
CetrorelixApproved drug: LabelIVF and assisted reproduction. Approved to prevent premature LH surges (early ovulation) during ovarian stimulation. In US phase 3 trials of 577 women, surges occurred in 0–1.9%; clinical pregnancy rates were 19.8–22.6% per attempt.
GanirelixApproved drug: LabelIVF and assisted reproduction. Approved to stop premature LH surges during ovarian stimulation. In the US label’s 463-woman trial, surges occurred in under 1%, with ongoing pregnancy in 20.3% per attempt.
VIPApproved drug: LabelErectile dysfunction, with phentolamine. Invicorp, injected into the penis, is licensed in the UK and several European countries. In label trials of 343 men, 73–74% of injections gave an erection suitable for sex vs 12–13% on placebo.

Tested in people 29

Studied in people, whatever the result: some worked, many didn’t or are unproven.

L-CarnitineApproved drug: TrialSperm quality in male infertility. Mixed: a meta-analysis of 8 oral trials found better sperm movement and shape, but no clear rise in pregnancy rates.
LiraglutideApproved drug: TrialPolycystic ovary syndrome (PCOS). Positive, not an approved use: in a 32-week placebo-controlled trial of 82 women with obesity and PCOS, liraglutide 3 mg cut weight 5.7% vs 1.4% and lowered a measure of male-type hormones (free androgen index). In a 26-week trial of 72 women, 1.8 mg made periods more regular than placebo.
GlutathioneApproved drug: TrialMale infertility (sperm quality). Small trial: in 20 men, muscle injections every other day for 2 months improved sperm movement and shape vs placebo in a crossover design. Pregnancy outcomes weren’t reported.
VesugenPreclinical: TrialErectile dysfunction from narrowed arteries. Unproven: a Russian report on 41 men says penile artery blood flow improved after a Vesugen course; it compared before and after only and gives no numbers in the abstract.
TeriparatideApproved drug: TrialHypoparathyroidism (low parathyroid hormone). Off-label: twice-daily injections kept calcium similar to calcitriol and calcium in 27 adults over 3 years, with normal urine calcium. Palopegteriparatide is the approved PTH(1–34) product for it.
CJC-1295 with DACHuman studies: TrialRaising growth hormone and IGF-1. Shown in healthy adults: one injection raised GH 2–10-fold for 6 days or more and IGF-1 1.5–3-fold for 9–11 days. No clinical benefit was measured.
IpamorelinHuman studies: TrialRaising growth hormone. Shown by IV in healthy men: each dose caused one GH pulse peaking at about 40 minutes, back to very low levels by 6 hours. Injection under the skin hasn’t been measured.
SermorelinHuman studies: TrialRaising GH and IGF-1 in older men. Mixed: twice-daily shots for 2 weeks raised GH and IGF-1 to young-adult levels in 10 older men, but nightly shots for 6 weeks in 11 men raised GH without changing IGF-1.
GHRP-6Human studies: TrialTesting for growth hormone deficiency. Studied, not approved: given once by IV with GHRH (growth-hormone-releasing hormone) to 250 adults, it separated GH-deficient patients (mean peak 4.1 mcg/L) from healthy people (59.2), with no side effects.
MacimorelinApproved drug: TrialTesting for diabetes insipidus (AVP deficiency). Negative: in 28 healthy volunteers it raised growth hormone but not copeptin, a marker of the water-balance hormone vasopressin, so it can’t replace current tests.
Melanotan 2Human studies: TrialErectile dysfunction. Positive in two tiny trials but never approved: single injections produced erections in 8 of 10 men (1998) and after 12 of 19 doses vs 1 of 21 on placebo (2000), with frequent nausea.
hCGApproved drug: TrialProtecting fertility on testosterone therapy. Small studies only: in 29 healthy men on testosterone, 250–500 IU every other day kept testicular testosterone near or above baseline for 3 weeks. Sperm data come from a 26-man records review.
Kisspeptin-10Human studies: TrialRaising LH and testosterone in men. Shown short term: IV doses raised LH within 30–45 minutes, and a 22.5-hour infusion raised testosterone from 16.6 to 24.0 nmol/L. Daily 8-hour under-the-skin infusions kept hormones up for 12 days.
Kisspeptin-10Human studies: TrialLow testosterone (secondary hypogonadism). Unproven: in 12 men with type 2 diabetes and low testosterone, an 11-hour IV infusion raised testosterone from 8.5 to 11.4 nmol/L. FDA judged the evidence insufficient for treatment.
Kisspeptin-10Human studies: TrialSexual desire and arousal. Not tested with kisspeptin-10: the well-known trials gave kisspeptin-54, a longer form, by 75-minute IV infusion to 32 women and 32 men with low desire, changing brain responses to sexual videos.
Kisspeptin-10Human studies: TrialFertility and IVF. Unproven for kisspeptin-10: IVF trials used kisspeptin-54, which triggered egg maturation in 95% of 60 high-risk women. Pump trials of kisspeptin-10 in fertility disorders are under way.
PT-141Approved drug: TrialErectile dysfunction. Unproven: small lab studies found nasal or injected doses caused erections; one 342-man nasal trial reported benefit, but that paper has a 2023 expression of concern. Not approved for men.
OxytocinApproved drug: TrialSexual desire and orgasm. Not shown: in a crossover trial with 8-week periods in 30 women with sexual problems, a nasal dose before sex helped no more than placebo; both improved.
OxytocinApproved drug: TrialBreast milk let-down. Not shown: in a trial of 51 mothers pumping milk for preterm babies, a nasal spray before pumping didn’t raise total milk output vs placebo.
OxytocinApproved drug: TrialVaginal dryness after menopause (gel). Promising but small: in a 96-woman trial, 8 weeks of nightly oxytocin vaginal gel improved the vaginal lining, its pH and symptoms of vaginal atrophy more than placebo, and a 20-woman pilot agreed. It isn’t an approved use.
GonadorelinApproved drug: TrialFertility in men lacking GnRH. Partly positive: pump therapy started sperm production about 5 months sooner than hCG with hMG in a pooled analysis of 420 men; sperm counts and pregnancy rates didn’t differ significantly.
PalopegteriparatideApproved drug: TrialHypoparathyroidism symptoms and quality of life. Positive: in PaTHway, symptom and functioning scores on a hypoparathyroidism-specific scale improved more than on placebo over 26 weeks, as did physical functioning on the SF-36 survey.
CosyntropinApproved drug: TrialLow-dose (1 mcg) adrenal test. Off-label: a meta-analysis found the 1 mcg and 250 mcg tests about equally accurate for pituitary-related adrenal insufficiency; both are better at confirming it than ruling it out.
LeuprolideApproved drug: TrialIVF and assisted reproduction. Off-label in the US. A single dose can replace hCG to mature eggs; in a Cochrane review, this cut ovarian hyperstimulation syndrome (OHSS) but lowered live births in fresh-embryo cycles.
CetrorelixApproved drug: TrialOvarian hyperstimulation syndrome (OHSS). Antagonist protocols (cetrorelix or ganirelix) cause less OHSS than long agonist protocols with similar live births: in a Cochrane review, OHSS risk fell from about 11% to 6–9%.
CetrorelixApproved drug: TrialEndometriosis. Unproven: in a pilot study of 15 women, 3 mg weekly for 8 weeks relieved symptoms in all and shrank disease in 9. No controlled trial followed.
CetrorelixApproved drug: TrialUterine fibroids before surgery. Unproven: in 20 women given a depot form for 6–8 weeks before surgery, the largest fibroid shrank by about a third in the 16 who responded. Not approved for this.
GanirelixApproved drug: TrialOvarian hyperstimulation syndrome (OHSS). In a 730-woman trial, OHSS occurred in 2.4% on ganirelix vs 5.9% with a buserelin long protocol. A Cochrane review found less OHSS with antagonists and similar live births.
GanirelixApproved drug: TrialIntrauterine insemination (IUI) cycles. Not approved for this. In 203 women having stimulated IUI, ganirelix cut premature LH rises to 3.9% from 28.0% on placebo, but pregnancy rates were the same (12.6% vs 12.0%).

Seen only in animals 2

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

FOXO4-DRIPreclinical: AnimalTestosterone and sperm in older men. Unproven in people: in naturally aged mice, it cleared senescent testosterone-making (Leydig) cells, eased the age-related drop in testosterone and improved sperm quality, in two studies from one Chinese university.
TestagenPreclinical: AnimalUnderactive thyroid after pituitary loss. In chickens whose pituitary gland was removed, 40 days of it raised thyroid-stimulating hormone and thyroid hormones and restored thyroid structure. Never tested in people or other mammals.

Claims without data 15

Promoted by sellers, clinics or users, with no study behind the claim.

ProstamaxPreclinical: No studyErectile function and libido. Unproven: no study has tested it for erections, libido or testosterone, in people or animals.
CJC-1295 (no DAC)Preclinical: CommunityBigger GH pulse paired with ipamorelin. Unproven for this pair: in 18 healthy men, GHRH plus a related GH-releasing peptide (GHRP-6) released more GH together than alone, but this exact pair has never been tested.
CJC-1295 (no DAC)Preclinical: No studyRaising growth hormone and IGF-1. Unproven for this peptide: no study has measured it. The human GH and IGF-1 rises often quoted come from CJC-1295 with DAC, a different, week-long-acting molecule.
CJC-1295 (no DAC)Preclinical: No studyGrowth hormone deficiency. Unproven: FDA found no study of any CJC-1295 form in people with GH deficiency (2024). People with complete deficiency wouldn’t respond, and approved GH treatments exist.
CJC-1295 with DACHuman studies: No studyGrowth hormone deficiency. Unproven: never tested in people with GH deficiency. FDA (2024) found no effectiveness data, noted complete deficiency wouldn’t respond, and pointed to approved GH treatments.
IpamorelinHuman studies: No studyGrowth hormone deficiency. Unproven: FDA found no study in people with GH deficiency (2024); the only GH data come from healthy men. Approved GH treatments exist.
Melanotan 2Human studies: No studyLow sexual desire in women. Unproven for melanotan II: one of its inventors reported raised desire in women (2005), but no controlled trial has been published. Its near-identical relative bremelanotide is approved for low desire in premenopausal women.
hCGApproved drug: CommunityRestarting testosterone after steroid cycles. Unproven: used during or after steroid cycles to restart natural testosterone; only case reports and reviews exist, no controlled trial. WADA bans hCG in male athletes.
Kisspeptin-10Human studies: CommunityRestarting testosterone after steroids. Unproven: used to try to restart natural testosterone, but no study has tested daily injections for this, and nonstop exposure blunted LH and FSH responses within 5 days.
PT-141Approved drug: CommunityLibido in men or after menopause. Unproven: users report it, but no published trial has tested it for low desire in men or in women after menopause, and the label excludes both groups.
GonadorelinApproved drug: CommunityProtecting the testes on testosterone therapy. Unproven: popular as an hCG substitute, but no trial has tested it with testosterone therapy. Each dose acts for minutes; the evidence comes from pumps pulsing every 90 minutes.
GonadorelinApproved drug: CommunityRestarting testosterone after steroids. Unproven: no study has tested injections for recovery after steroid use, and continuous or too-frequent exposure suppresses LH and FSH rather than raising them.
TriptorelinApproved drug: CommunityRestarting testosterone after steroid use. Unproven: some users inject a single small dose after a steroid cycle to try to restart their own testosterone. No study has tested this, and repeated or depot dosing shuts testosterone down instead.
PalopegteriparatideApproved drug: No studyLow calcium right after neck surgery. Not studied: the US label says it wasn’t tested for acute hypoparathyroidism after surgery, and its dosing scheme assumes calcium was first stabilized.
TestagenPreclinical: No studyTestosterone, sperm and libido. Unproven: no published study has tested it on testosterone, sperm, libido or the testes, in animals or people. Its developers list male reproductive function but cite no such study.

Stomach and gut 39

In more detail: peptides for gut health.

On a label 10

Approved uses, from a product label somewhere in the world.

GlucagonApproved drug: LabelDiagnostic aid in radiology. Approved for adults to relax the stomach, small bowel or colon during radiology exams. After an IV dose, relaxation starts within about a minute and lasts roughly 9–17 minutes.
TeduglutideApproved drug: LabelShort bowel syndrome. Approved for adults (and children) who depend on IV nutrition or fluids. In STEPS, 63% vs 30% on placebo cut weekly IV volume by at least 20% over 24 weeks.
TeduglutideApproved drug: LabelComing off IV nutrition completely. Possible for a minority: in the extension studies, 13 of 88 adults stopped IV support entirely within 30 months; most others needed less but not none.
LinaclotideApproved drug: LabelIBS with constipation. Approved for adults in the US, EU, UK, Canada, Australia and Japan. In two US trials, 34% met the FDA goal (less belly pain plus more complete bowel movements) vs 14–21% on placebo.
LinaclotideApproved drug: LabelChronic idiopathic constipation. Approved for adults in the US, Canada, Australia and Japan, not the EU or UK. In two 12-week trials, 15–20% met the main bowel-movement goal vs 3–6% on placebo.
LinaclotideApproved drug: LabelBloating in IBS with constipation. Covered by the IBS-C approval. In a 12-week trial of 614 adults, a combined bloating, discomfort and pain score fell 1.9 vs 1.2 points on placebo (0–10 scale).
PlecanatideApproved drug: LabelChronic idiopathic constipation. Approved for adults in the US (2017) and Canada (2024). In two 12-week trials, 21% on 3 mg were durable responders, with more complete bowel movements most weeks, vs 10–13% on placebo.
PlecanatideApproved drug: LabelIBS with constipation. Approved for adults in the US (2018) and Canada (2019). In two 12-week trials, 21–30% met the combined belly-pain and bowel-movement goal vs 14–18% on placebo.
Somatropin (HGH)Approved drug: LabelShort bowel syndrome. Zorbtive was approved in 2003 for 4 weeks with a special diet but has no current US listing. In 41 adults, GH plus glutamine cut weekly IV nutrition most: 7.7 vs 3.8 liters.
ThymogenApproved drug: LabelChronic atrophic gastritis. An oral gel form is registered in Russia for this. In a placebo-controlled trial, stomach glands per mm² rose 26.1% from baseline, significantly more than with placebo.

Tested in people 15

Studied in people, whatever the result: some worked, many didn’t or are unproven.

GlucagonApproved drug: TrialFood stuck in the esophagus. Not shown: in the only randomized trial (43 people), IV diazepam plus glucagon cleared the blockage in 38% vs 32% on placebo. A Cochrane review found the evidence inadequate.
BPC-157Preclinical: TrialUlcerative colitis (inflammatory bowel disease). Not shown: in a 53-person placebo-controlled enema trial known only from a 2005 abstract, the difference from placebo could have been chance; FDA judged the data inadequate.
LarazotideHuman studies: TrialCeliac disease symptoms on a gluten-free diet. Mixed: in a 12-week trial of 342 adults with ongoing symptoms, 0.5 mg three times daily eased symptoms more than placebo; 1 and 2 mg didn’t.
LarazotideHuman studies: TrialCeliac disease: phase 3 outcome. Stopped: the CeDLara phase 3 trial (307 adults, 0.25 or 0.5 mg) was ended by its sponsor in July 2022 after an interim analysis. No results were posted; it was never approved.
LarazotideHuman studies: TrialProtection when gluten is eaten. Unproven: in gluten-challenge trials of 86 and 184 people (2–6 weeks), low doses limited symptoms and antibody rises were smaller, but gut permeability didn’t clearly change. It isn’t a substitute for the diet.
TeduglutideApproved drug: TrialCrohn’s disease. Not shown: in an 8-week pilot trial of 100 adults with active Crohn’s disease, response was only numerically higher than placebo (44% vs 32% at the highest dose). Not an approved use.
LinaclotideApproved drug: TrialBowel preparation for colonoscopy. Not an approved use. A 2026 analysis of 8 trials (3,591 people), mostly from China, found that adding it to polyethylene glycol prep modestly improved bowel cleanliness.
PlecanatideApproved drug: TrialFunctional constipation. Positive in a 12-week phase 3 trial of 648 adults in China: 23.5% were durable responders vs 10.2% on placebo. Functional constipation largely overlaps with chronic idiopathic constipation.
PlecanatideApproved drug: TrialBloating in IBS with constipation. In a later analysis of the IBS-C trials, adults with moderate to severe bloating saw it fall 1.7 vs 1.3 points on placebo (0–10 scale). The label makes no bloating claim.
IpamorelinHuman studies: TrialGut recovery after bowel surgery. Not shown: in a 114-patient IV trial, a first solid meal came at 25.3 vs 32.6 hours on placebo, a gap that could be chance. A 320-patient trial (2014) hasn’t been published.
OctreotideApproved drug: TrialBleeding from gut angiodysplasia. Promising, not approved: in an open-label trial of 62 adults needing repeated transfusions, a year of the monthly depot cut transfusions to 11.0 from 21.2 units with standard care.
OxytocinApproved drug: TrialIBS and constipation. Not shown: in a 13-week trial of 59 women with hard-to-treat constipation, nasal oxytocin didn’t relieve constipation more than placebo, though belly pain eased slightly. An IV infusion raised the gut-pain threshold in 26 people with IBS.
SemaxApproved drug: TrialStomach ulcers. Unproven: among 32 adults with hard-to-heal peptic ulcers, 89.5% healed by day 14 with 10 days of nasal Semax added to usual drugs, vs 30.8% on usual drugs alone. No placebo.
IcotrokinraApproved drug: TrialUlcerative colitis. Promising, not approved: in a 12-week phase 2b trial of 252 adults, clinical response was 54.7–63.5% vs 27.0% on placebo, and remission 30.2% vs 11.1% at 400 mg. Reported only as an abstract.
IcotrokinraApproved drug: TrialCrohn’s disease. Unproven: a phase 2b/3 trial in about 1,100 adults began in October 2025, with first results expected around 2028.

Seen only in animals 8

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

PancragenPreclinical: AnimalPancreatitis and pancreas repair. Only cell work: in the developers’ 2012–2013 studies of aging human pancreatic cell cultures, it raised markers of cell renewal and maturation. They suggest pancreatitis use, but no animal or human pancreatitis study exists.
BPC-157Preclinical: AnimalStomach and gut lining protection. Unproven in people: in rats it reduced stomach and gut damage from high-dose painkillers such as aspirin and sped healing of surgically made colon fistulas (abnormal channels).
KPVPreclinical: AnimalUlcerative colitis and Crohn’s disease. Unproven in people: KPV in drinking water reduced colitis in two mouse models, and FDA found no study of KPV in humans for any condition.
LarazotideHuman studies: AnimalColitis, arthritis and fatty liver. Unproven in people: in mice and rats it lessened colitis, delayed arthritis onset, limited fatty liver and reduced gut leakiness in pancreatitis. None of these uses has been tested in human trials.
PlecanatideApproved drug: AnimalColitis (gut inflammation). Unproven: in mouse models of colitis, oral plecanatide eased gut inflammation about as well as standard drugs (2015). It hasn’t been tested for colitis in people.
LivagenPreclinical: AnimalDigestion in older age. In old rats given it by mouth for 2 weeks, gut enzyme activity moved toward young-rat levels, while in young rats it fell. Not studied in people.
IGF-1 LR3Preclinical: AnimalGut growth and repair. Unproven in people: in rats, 2 weeks of infusion enlarged the gut by up to 43%, and it eased malabsorption after removal of most of the small bowel. Never tested for gut disease in humans.
IGF-1 DESPreclinical: AnimalGut recovery after bowel surgery. Unproven in people: in rats with 80% of the small bowel removed, it improved weight gain and protein balance over 7 days, matching IGF-1 given at 2.5 times the dose.

Claims without data 6

Promoted by sellers, clinics or users, with no study behind the claim.

PancragenPreclinical: No studyDigestion and pancreatic enzymes. No study has measured digestive enzymes or digestion in people or animals given it.
BPC-157Preclinical: CommunityGut health, IBS and ulcers. Unproven: FDA found compounding pharmacies, clinics and med spas promoting it for irritable bowel syndrome, ulcers and gut balance. No human study has tested it for these.
KPVPreclinical: CommunityGut inflammation and leaky gut. Unproven: no human study exists. FDA found websites selling it for gut health, irritable bowel syndrome and Crohn’s disease as injections, capsules, creams and nasal sprays.
LarazotideHuman studies: No study“Leaky gut” in general. Unproven: it was designed to tighten the gut lining, but the larger celiac trials didn’t clearly reduce permeability, and no trial has tested it for leaky gut outside celiac disease or COVID-related illness.
TeduglutideApproved drug: No studyLeaky gut or gut repair without short bowel. Unproven: no study has tested it for leaky gut, IBS or general gut health. Its label warns that it may speed the growth of polyps and tumors.
OvagenPreclinical: No studyGut lining and digestion. Guides claim it protects the gut lining and aids digestion. No published study has tested this in animals or people.

Immune system and infections 30

On a label 8

Approved uses, from a product label somewhere in the world.

Somatropin (HGH)Approved drug: LabelHIV-associated wasting. Serostim is approved alongside HIV medicines. In a 12-week trial of 178 adults, weight rose 1.6 kg and lean mass 3.1 kg more than on placebo, and treadmill work output rose 13%.
DesmopressinApproved drug: LabelBleeding in hemophilia A and von Willebrand disease. Approved (injection, Stimate spray) for mild hemophilia A and type 1 von Willebrand disease with factor VIII above 5%, around surgery or bleeds; clotting factors rise within 30 minutes.
CosyntropinApproved drug: LabelInflammatory bowel disease and arthritis flares. UK only: Synacthen Depot is licensed for short-term use where steroids would be used, such as ulcerative colitis, Crohn’s disease or rheumatoid arthritis, especially when steroid pills don’t suit.
Thymosin Alpha-1Approved drug: LabelFlu vaccine add-on for weak immunity. Italy’s only approved use: twice weekly for 4 weeks, starting with each of two flu shots 8 weeks apart. Small trials measured antibodies, not flu cases; FDA found the evidence insufficient.
ThymalinApproved drug: LabelImmune deficiency with serious infections. Registered in Russia for weakened immunity in adults and children from 6 months with acute or chronic infections, pus-forming or septic infections, or impaired healing. Supporting studies are mostly small and Russian.
ThymogenApproved drug: LabelInfections with weakened immunity. Registered in Russia (injection) as an add-on for viral and bacterial infections with suppressed immunity, such as hepatitis, pneumonia, skin infections, burns and wound infections. Supporting studies are mostly small and Russian.
ThymogenApproved drug: LabelColds, flu and other airway infections. The Russian nasal spray is registered to prevent and treat upper airway infections. A 1993 study in a military unit reported fewer infections, but its abstract gives no numbers.
ThymogenApproved drug: LabelImmune recovery after surgery, chemotherapy or radiation. Registered in Russia for this. A small Russian placebo-controlled study in older patients before cancer surgery reported fewer complications, but its abstract gives no numbers.

Tested in people 9

Studied in people, whatever the result: some worked, many didn’t or are unproven.

LarazotideHuman studies: TrialLong COVID. Unknown: a 107-person placebo-controlled trial in people aged 7–50, taking it by mouth for 21 days, finished in June 2026; no results have been posted or published.
GHRP-2Approved drug: TrialRecovery in critical illness. Unproven: in men in long-term intensive care, 5-day infusions restored GH and IGF-1, but GHRP-2 alone didn’t reduce protein breakdown (33 men). FDA lists deaths of critically ill study patients among reported events.
Thymosin Alpha-1Approved drug: TrialSepsis. Not shown: in TESTS (1,106 adults with sepsis), 28-day deaths were 23.4% on 1.6 mg twice daily for 7 days vs 24.1% on placebo. An earlier, smaller single-blind trial had hinted at benefit.
Thymosin Alpha-1Approved drug: TrialCOVID-19. Unproven: in a US trial of 49 hospitalized adults, faster recovery wasn’t statistically significant. An Indian placebo trial of 105 reported fewer deaths in severe cases; FDA judged the evidence insufficient.
Thymosin Alpha-1Approved drug: TrialHIV infection. Not shown: FDA’s 2024 review found five studies, none showing effects on viral load, AIDS-related illness or survival; rises in CD4 immune cells were inconsistent.
ThymalinApproved drug: TrialCOVID-19. Unproven: in a 92-person open-label Russian trial, 5 daily injections added to standard care raised lymphocyte counts and lowered inflammation markers faster; no one died in either group.
ThymalinApproved drug: TrialTuberculosis and other serious infections. Unproven by modern standards: small Soviet-era, Russian and Ukrainian studies added it to treatment for tuberculosis, lung abscess or pancreatitis and reported faster recovery; the abstracts describe no blinding or placebo.
VIPApproved drug: TrialCIRS (mold-related illness). Unproven: in one open-label study, 20 people with CIRS who had first finished 10 other treatment steps reported symptoms falling to healthy levels over 18 months of nasal VIP. No control group.
LL-37Human studies: TrialTreating infections. Unproven: it kills many bacteria in lab dishes, though salty, tissue-like conditions blunt it. In mildly infected foot ulcers, it didn’t cut bacteria more than placebo.

Seen only in animals 6

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

ARA-290Human studies: AnimalProtecting transplanted organs and islet cells. Unproven in people: it protected transplanted islet cells and kidney grafts in rats and in laboratory work. It holds orphan designations for these uses but no trial has reported.
ChonlutenPreclinical: AnimalInflammation. In a 2022 Italian lab study, human immune cells in a dish released less of the inflammatory signal TNF after a bacterial trigger; with related peptides, IL-6 also fell. Not tested in animals or people.
TestagenPreclinical: AnimalImmune and thymus function. In the same chickens it normalized immune and blood-clotting measures and helped restore the thymus. Not tested in people.
SelankApproved drug: AnimalImmune support and flu prevention. Unproven in people: in flu-infected lab animals, survival was highest when it was given before infection (2009). A 14-day study in anxious patients found shifts in blood cytokines (immune signals) but didn’t track infections.
VIPApproved drug: AnimalAutoimmune and inflammatory disease. Unproven in people: in mice, VIP injections prevented experimental arthritis and eased a Crohn’s-like colitis. No human trial has tested it for these.
VilonPreclinical: AnimalImmune support. Unproven: in cell cultures it raised interleukin-2 gene activity and pushed thymus cells toward helper T cells; the one human report on immune cells, in diabetes, gave no numbers.

Claims without data 7

Promoted by sellers, clinics or users, with no study behind the claim.

KPVPreclinical: No studyMast cell activation and histamine problems. Unproven: FDA found it promoted for mast cell activation syndrome and histamine intolerance, with no study behind those claims in people or animals.
KPVPreclinical: No studyInfections, Lyme disease and mold illness. Unproven: promoted for these online. In lab dishes the peptide slowed growth of one bacterium and one yeast; no infection has been treated with it in a person.
Thymosin Alpha-1Approved drug: No studyImmune support, Lyme disease, chronic fatigue. Unproven: no trial has tested it as everyday immune support in healthy people. FDA found no Lyme disease studies and no evidence for chronic fatigue syndrome (ME/CFS); no long COVID trial appears on PubMed.
ThymalinApproved drug: No studyImmune boost or anti-aging in healthy people. Unproven: no controlled study has tested it in healthy people for general immune support or anti-aging. The label covers only immune deficiency linked to disease or treatment.
VIPApproved drug: CommunityLong COVID and brain fog. Unproven: nasal VIP is promoted for long COVID and brain fog, but no trial has tested it for either. The only nasal study is the 20-person CIRS report.
LL-37Human studies: No studyChronic infections, biofilms and immune support. Unproven: no human study has tested LL-37 for these. FDA found too little safety information to know whether it causes harm when given to people.
ThymulinHuman studies: CommunityImmune support and thymus aging. Sold for this, and blood thymulin does fall with age, but no study has given thymulin to healthy adults for immune support or aging.

Aging and longevity 35

In more detail: peptides for aging and longevity.

Tested in people 9

Studied in people, whatever the result: some worked, many didn’t or are unproven.

NAD+Human studies: TrialRaising blood NAD+ levels. Partly: during a 750 mg IV drip over 6 hours in 8 men, blood NAD+ didn’t rise for 2 hours, then rose about 400% above baseline by the end. Uptake into cells is unmeasured.
NAD+Human studies: TrialEnergy and chronic fatigue. Mixed: in a 26-person crossover trial of oral NADH, the reduced form, 31% responded vs 8% on placebo. Injected NAD+ hasn’t been tested for energy or fatigue.
GlutathioneApproved drug: TrialRaising body glutathione levels. By mouth, 1,000 mg a day for 6 months raised levels 30–35% in blood cells and plasma (54 adults). Injected doses leave the blood within minutes; effects inside cells are unmeasured.
EpithalonPreclinical: TrialLongevity and lifespan. Unproven: the human data are for Epithalamin, the parent pineal extract, from one group: in 266 people over 60, courses were linked to 1.6–1.8 times lower death rates over 6–8 years. Not double-blind.
VesugenPreclinical: TrialSlowing aging (biological age). Unproven: in 32 adults aged 41–83 with brain disorders, Vesugen improved biological-age scores more than Pinealon, but also raised oxidation and lowered blood stem cells; no placebo group.
Somatropin (HGH)Approved drug: TrialAnti-aging in healthy older adults. Not recommended: in 18 trials, 220 people given GH for about 27 weeks lost 2.1 kg of fat and gained 2.1 kg of lean mass, but had more swelling, joint pain and carpal tunnel.
Somatropin (HGH)Approved drug: TrialReversing biological age. Unproven: in an uncontrolled pilot, 9 men given GH with DHEA and metformin for a year had epigenetic age estimates about 1.5 years below baseline. A larger trial hasn’t reported.
PinealonPreclinical: TrialSlowing brain and body aging. Unproven: small Russian reports (32 adults with chronic brain disorders; train crews taking 100 mcg capsules twice daily for 2 weeks) describe better “biological age” scores, without placebo groups or full numbers.
ThymalinApproved drug: TrialLongevity in older adults. Unproven: in 266 people over 60 studied by its developers and partners, courses in the first 2–3 years were linked to 2.0–2.1 times lower death rates over 6–8 years. Not double-blind.

Seen only in animals 18

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

5-Amino-1MQPreclinical: AnimalRaising NAD+ for energy and aging. Unproven in people: in fat cells in a dish it raised NAD+, a cell energy carrier, about 1.2–1.6-fold. Whether capsules or shots raise NAD+ in a person hasn’t been measured.
NAD+Human studies: AnimalAnti-aging and longevity. Unproven in people: raising NAD+ improved metabolic and mitochondrial measures in rodents. A 2026 review of 33 human studies found no outcome trial of injected NAD+; oral precursors gave mixed results.
MOTS-cPreclinical: AnimalLongevity and anti-aging. Unproven: mice started on it late in life had better grip strength and walking, with a nonsignificant trend to longer life. A MOTS-c gene variant is linked with long life in Japanese people.
SS-31Approved drug: AnimalAnti-aging and longevity. Unproven in people: in old mice, one injection restored muscle energy production within an hour, 8 days raised endurance, and 8 weeks reversed age-related decline in heart relaxation.
EpithalonPreclinical: AnimalTelomeres and cell aging. Unproven in people: it lengthened telomeres, the protective caps on chromosomes, in human cells in a dish, as an independent 2025 study confirmed. No published study has measured them in people taking it.
HumaninPreclinical: AnimalLongevity and healthy aging. Unproven: extra humanin lengthened worm lifespan, and twice-weekly HNG improved metabolic health markers in middle-aged mice. In people, studies disagree on whether blood levels fall or rise with age.
FOXO4-DRIPreclinical: AnimalClearing senescent (worn-out) cells. Unproven in people: in cell cultures and mice it pushed senescent cells to self-destruct while largely sparing healthy cells. No one has been given it in a published study.
VesugenPreclinical: AnimalAtherosclerosis and blood vessel aging. Unproven: in cell cultures it raised the cell-division marker Ki-67 in aging vessel-lining cells and normalized endothelin-1 in atherosclerosis models. No controlled human trial has tested it.
CarnosineHuman studies: AnimalAnti-aging and sugar damage to proteins. Unproven: it blocks glycation and oxidative damage in lab and animal studies, and one diabetes trial saw lower blood AGE markers, but no human study has measured aging.
LivagenPreclinical: AnimalAging and gene activity. In developer and Tbilisi studies (2002–2007), blood cells from people aged 75–91, grown in a dish, showed looser chromatin and active ribosomal genes. Whether this matters in a living person is unknown.
LivagenPreclinical: AnimalDNA and chromosome protection. In Tbilisi lab studies (2008–2017), cultured blood cells from older people and from patients with atherosclerosis or breast cancer showed fewer chromosome-damage markers with it. Not tested in a person.
ProstamaxPreclinical: AnimalAging and chromatin “reactivation”. Unproven: in blood cells from people aged 75–88, treated in a dish, it loosened tightly packed chromatin and activated ribosome genes (Khavinson 2004). No study has given it to people.
GHK-CuHuman studies: AnimalAnti-aging genes, longevity and brain health. Unproven: claims rest on computer analyses of gene-activity databases and rodent studies, much of it from GHK’s discoverer. No human study has tested it for aging, memory, mood or lifespan.
TestagenPreclinical: AnimalAging and gene activity. In 2011 and 2013 test-tube studies by its developers, it entered cell nuclei and bound DNA and histones, which they link to gene control in aging. No effect on aging has been measured.
DSIPApproved drug: AnimalAnti-aging and longevity. Unproven: in mice given monthly Deltaran courses for life, average lifespan didn’t change, but the longest-lived survived longer and tumors were rarer (2003). Never tested in people.
PinealonPreclinical: AnimalAntioxidant protection. Unproven: in cell cultures it limited cell-damaging reactive oxygen species, but a small Russian study of pinealon and a related peptide in people found pro-oxidant activity, the opposite effect.
CortagenPreclinical: AnimalAntioxidant protection. Unproven: in rats it lowered markers of fat and protein oxidation, though antioxidant activity in blood and brain cortex also fell.
VilonPreclinical: AnimalSlowing aging and extending lifespan. Unproven in people: in a 2000 study of female mice injected under the skin from 6 months of age, its developers reported longer lives, more stamina and fewer spontaneous tumors.

Claims without data 8

Promoted by sellers, clinics or users, with no study behind the claim.

SemaglutideApproved drug: No studyMicrodosing for inflammation or longevity. Unproven: no study has tested small “microdoses” for inflammation, aging or general wellness. Benefits were shown at labeled doses for weight, diabetes, heart, kidney and liver outcomes.
TirzepatideApproved drug: No studyMicrodosing for inflammation or longevity. Unproven: no study has tested small “microdoses” of tirzepatide for inflammation, aging or general wellness. Benefits were shown at labeled doses for diabetes, weight, sleep apnea and heart outcomes.
RetatrutideHuman studies: No studyMicrodosing for longevity or wellness. Unproven: no study has tested small “microdoses” of retatrutide for aging, inflammation or general wellness. Trials used 1–12 mg weekly for obesity and diabetes.
AOD9604Human studies: No studyBone, skin, mood and anti-aging claims. Unproven: FDA found clinics promoting it for osteoporosis, skin care, depression and anti-aging. No study has tested it for these; a rat study raised a possible bone concern.
L-CarnitineApproved drug: CommunityEnergy and fatigue (wellness injections). Unproven: users report more energy from shots, but no trial has tested injections in healthy people; in dialysis patients, carnitine didn’t ease fatigue (2 trials, 353 people).
SurvodutideHuman studies: No studyMicrodosing for longevity or wellness. Unproven: no study has tested small “microdoses” of survodutide for aging, inflammation or general wellness. Trials used weekly doses up to 6.0 mg for obesity, diabetes and liver disease.
GlutathioneApproved drug: CommunityDetox, energy and immunity (wellness drips). Unproven: users report more energy and a “detox” feeling from IV or muscle shots, but no controlled trial has tested these claims.
CJC-1295 (no DAC)Preclinical: CommunityAnti-aging, skin and joints. Unproven: FDA found websites promising stronger bones, better skin and joints, mood, memory and libido (2024). None of these has been studied for any form of CJC-1295.

Cancer and cancer care 36

On a label 9

Approved uses, from a product label somewhere in the world.

GlutathioneApproved drug: LabelPreventing chemotherapy nerve damage. Approved in Italy to prevent nerve damage from cisplatin-type drugs. Small trials with cisplatin and oxaliplatin found less damage, but a 185-person trial with paclitaxel and carboplatin found no benefit.
OctreotideApproved drug: LabelDiarrhea and flushing from carcinoid tumors. Approved for symptom control in metastatic carcinoid tumors. In a 6-month trial the depot controlled stools and flushing as well as daily injections, though 50–70% needed some extra short-acting doses.
OctreotideApproved drug: LabelSlowing advanced midgut neuroendocrine tumors. A UK and EU depot use, not a US one. In PROMID (85 people), the median time before tumors grew was 14.3 vs 6.0 months on placebo; longer survival wasn’t shown.
TriptorelinApproved drug: LabelAdvanced prostate cancer. Trelstar is approved for advanced prostate cancer. Testosterone fell to castrate level (under 50 ng/dL) by day 29 in 91.2–97.7% of men across the three depot strengths.
TriptorelinApproved drug: LabelEarly breast cancer before menopause. Licensed in the UK with tamoxifen or an aromatase inhibitor. In SOFT and TEXT (4,690 women), exemestane plus ovarian suppression (triptorelin, surgery or radiation) gave 91.1% 5-year disease-free survival vs 87.3% with tamoxifen plus suppression.
LeuprolideApproved drug: LabelAdvanced prostate cancer. Approved as depots every 1–6 months and as daily injections. Testosterone reached castrate level within about a month in 94–98.5% of men; in 1984, daily injections matched diethylstilbestrol with fewer side effects.
LeuprolideApproved drug: LabelBreast cancer before menopause. Licensed in the UK with tamoxifen or an aromatase inhibitor, not in the US. In the TABLE trial (599 women), a 3-month depot matched CMF chemotherapy for recurrence-free survival over 5.8 years.
LeuprolideApproved drug: LabelProtecting the ovaries during chemotherapy. Licensed in the UK (Prostap SR). In a trial of 330 women with breast cancer, goserelin or leuprorelin during chemotherapy cut ovarian failure at 12 months to 10.3% from 44.5%.
ThymalinApproved drug: LabelImmune and blood recovery after cancer treatment. The Russian label also covers suppressed immunity and blood cell production after chemotherapy or radiotherapy, and lasting thymus damage. The registration data haven’t been published in journals.

Tested in people 12

Studied in people, whatever the result: some worked, many didn’t or are unproven.

VesugenPreclinical: TrialMouth sores after cancer treatment. Unproven: in 22 older adults with chemotherapy-related mouth inflammation, adding Vesugen and another supplement to usual care was reported to help; the abstract gives no numbers or comparison group.
LinaclotideApproved drug: TrialColorectal cancer prevention. Unproven: in healthy volunteers, the approved capsules didn’t reliably activate their target in the colon lining, the researchers concluded. A phase 2 trial in people with colorectal tumors hasn’t reported results.
MacimorelinApproved drug: TrialCancer cachexia (weight and appetite loss). Unproven: in a 1-week pilot of 15 patients, daily doses didn’t meet weight, IGF-1 or quality-of-life targets more often than placebo; no related side effects were reported.
Melanotan 1Approved drug: TrialSunburn and skin cancer protection. Unproven against cancer: in 65 fair-skinned volunteers, 3 months of injections raised melanin and cut sunburn cells after UV by more than half in the fairest. No study has measured skin cancer rates.
MatrixylHuman studies: TrialPreventing skin damage from radiotherapy. Negative: in 20 patients having breast radiotherapy, a cream with Matrixyl and two other actives did no better than a dexpanthenol lotion, with more itch and one suspected allergic reaction.
TriptorelinApproved drug: TrialProtecting the ovaries during chemotherapy. Positive for early menopause: in 281 women with breast cancer, adding triptorelin to chemotherapy cut early menopause at 1 year to 8.9% vs 25.9%. Later pregnancy rates didn’t differ significantly.
Thymosin Alpha-1Approved drug: TrialAdd-on cancer treatment. Unproven: in a 488-person melanoma trial with chemotherapy, median survival was 9.4 months vs 6.6 without it, a gap that could be chance (P=0.08). FDA found no clear benefit in liver or lung cancer.
Thymosin Alpha-1Approved drug: TrialLung inflammation from radiotherapy. Unproven: given weekly to 69 people during and after chemoradiotherapy for lung cancer, it was linked to less moderate or worse radiation lung inflammation than in 69 earlier patients (36.2% vs 53.6%). There was no randomized control group.
LL-37Human studies: TrialMelanoma, injected into skin tumors. Unproven: a US phase 1/2 study gave weekly tumor injections to only 3 patients; one stopped for lack of effect, and the posted response results are unclear.
VilonPreclinical: TrialColon and rectal cancer, alongside treatment. Unproven: a preliminary Russian report in older adults with stage III bowel cancer recommends it to improve 2-year survival and cut complications, but its abstract gives no numbers or comparison.
ThymogenApproved drug: TrialAIDS-related Kaposi sarcoma. Not effective: in a 202-person placebo-controlled phase 3 trial of the IM862 nose drops, responses were 23% vs 21%, and tumors progressed sooner (median 16 vs 35 weeks).
ThymogenApproved drug: TrialProstate and kidney cancer. Not effective: as IM862 it didn’t slow disease progression vs placebo in 71 men with prostate cancer, and none of 25 people with kidney cancer had a tumor response.

Seen only in animals 15

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

EpithalonPreclinical: AnimalCancer prevention. Unproven: some mouse and rat studies from its developers report fewer tumors. FDA calls them too limited and notes that switching on telomerase could, in theory, raise cancer risk.
FOXO4-DRIPreclinical: AnimalProtection from chemotherapy damage. Unproven in people: in mice given the chemotherapy drug doxorubicin, it limited weight loss and the rise in a liver-damage marker. It hasn’t been tested in anyone having chemotherapy.
CardiogenPreclinical: AnimalCancer (tumor growth). Unproven in people: in old rats with a transplanted sarcoma, injections slowed tumor growth in a dose-dependent way by causing bleeding and cell death inside the tumor.
PNC-27Preclinical: AnimalCancer treatment. Unproven in people: it killed many cancer cell lines in culture and slowed human pancreatic tumors and leukemia in mice. No person has been given it in a published study.
PNC-27Preclinical: AnimalPancreatic cancer. Unproven in people: nude mice carrying a highly metastatic human pancreatic tumor were treated successfully, in reports from the laboratory that designed the peptide.
PNC-27Preclinical: AnimalAcute myeloid leukemia. Unproven in people: an independent cancer center reported in 2020 that it killed leukemia cells, including the stem-like cells that drive relapse, in mice while sparing normal blood stem cells.
PNC-27Preclinical: AnimalOvarian cancer. Unproven in people: cells taken from women with ovarian cancer were killed when treated outside the body, and the peptide added to paclitaxel in cell studies. No trial followed.
PNC-27Preclinical: AnimalCervical cancer. Unproven in people: a 2025 cell study reported it killed cervical cancer cells while leaving normal cervical cells intact.
PNC-27Preclinical: AnimalSparing normal cells. The central claim, shown only in cells and mice: normal cells carry little HDM-2 in their outer membrane, so the peptide forms no pores in them. Untested in people.
KPVPreclinical: AnimalLowering cancer risk. Unproven: in mice prone to colitis-linked bowel tumors, KPV reduced tumor number and size. FDA found no cancer studies of KPV and no human data of any kind.
PlecanatideApproved drug: AnimalColon cancer prevention. Unproven: in mice prone to inflammation-driven colon tumors, plecanatide in the diet reduced precancerous growths (2017). No human study has tested it for this.
HexarelinHuman studies: AnimalMuscle wasting from chemotherapy. Unproven in people: in rats given cisplatin, a cancer drug, it limited damage to muscle mitochondria, the cells’ energy producers. It hasn’t been tested in people.
VilonPreclinical: AnimalCancer prevention. Unproven and mixed: it cut chemically induced bladder tumors in rats (56% vs 75.5%), but in mice bred to get breast cancer, more treated mice had multiple tumors.
ThymogenApproved drug: AnimalAnti-aging and cancer prevention. Unproven in people: in female rats, monthly courses lowered tumor rates after radiation exposure and lengthened life (Anisimov 1992). No human study has tested this.
ThymulinHuman studies: AnimalCancer immunotherapy response. Unproven in people: a 2026 mouse study reports thymulin damping age-related inflammation and improving responses to an anti-PD-L1 cancer drug in older mice.

Alcohol, smoking and drugs 12

On a label 1

Approved uses, from a product label somewhere in the world.

DSIPApproved drug: LabelStress and alcohol withdrawal (Russia). Deltaran nose drops are registered in Russia, as part of combined treatment, for stress-related states and for alcohol withdrawal and craving. The label calls the mechanism unknown; no placebo-controlled Deltaran trial appears on PubMed.

Tested in people 8

Studied in people, whatever the result: some worked, many didn’t or are unproven.

SemaglutideApproved drug: TrialCutting alcohol use. Unproven: in a 9-week trial of 48 adults with alcohol use disorder, low doses reduced craving and drinks per drinking day, but not the number of drinking days. Larger trials are under way.
ExenatideApproved drug: TrialAlcohol use disorder. Not shown: in a 26-week trial of 127 people, weekly exenatide didn’t reduce heavy drinking days vs placebo; an exploratory look found less drinking in those with obesity.
ExenatideApproved drug: TrialQuitting smoking. Promising, unproven: in a 6-week pilot of 84 smokers using nicotine patches, 46% on weekly exenatide vs 27% on placebo weren’t smoking, with less weight gain. A larger trial is unpublished.
DulaglutideApproved drug: TrialCutting alcohol use. Unproven: in a secondary analysis of a 12-week smoking-cessation trial, the 151 participants who drank and finished treatment drank 29% less on dulaglutide than on placebo.
DulaglutideApproved drug: TrialQuitting smoking. Not shown: in a 12-week trial of 255 smokers also taking varenicline, 63% on dulaglutide vs 65% on placebo had quit, though weight fell 1.0 kg instead of rising 1.9 kg.
PemvidutideHuman studies: TrialAlcohol use disorder. Promising: in RECLAIM (100 adults with a BMI over 25), heavy drinking days fell by 4.2 a week vs 2.75 on placebo over 24 weeks, per a July 2026 company release; not yet published.
LinaclotideApproved drug: TrialOpioid-induced constipation. Not approved for this. In an 8-week phase 2 trial of 254 adults taking opioids for non-cancer pain, weekly bowel movements rose 2.9–3.5 vs 1.6 on placebo. No phase 3 result is published.
DSIPApproved drug: TrialOpioid withdrawal. Unproven: in open studies without control groups, IV DSIP eased opioid withdrawal in 97% of evaluable patients (60 enrolled, 1984), but only 2 of 7 finished a 1998 detox course.

Seen only in animals 1

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

SelankApproved drug: AnimalAlcohol and opioid withdrawal. Unproven in people: single injections eased withdrawal anxiety in alcohol-dependent rats, without cutting their drinking, and eased morphine-withdrawal signs in rats. No human study has tested this.

Claims without data 2

Promoted by sellers, clinics or users, with no study behind the claim.

MazdutideApproved drug: No studyCutting alcohol use. Unproven: a 308-person placebo-controlled trial in alcohol use disorder finished in May 2026 without published results. No other human data exist.
NAD+Human studies: CommunityAddiction and withdrawal (IV drips). Unproven: clinics promote IV NAD+ for alcohol and drug withdrawal, and users report relief, but no controlled study has been published.

Eyes 9

On a label 2

Approved uses, from a product label somewhere in the world.

OctreotideApproved drug: LabelDiarrhea from VIP-secreting tumors (VIPomas). Approved to control the profuse watery diarrhea of VIPomas, rare tumors that release the gut hormone VIP. The US labels say its effect on tumor size or growth hasn’t been shown.
SemaxApproved drug: LabelOptic nerve disease. The 0.1% drops are registered in Russia for optic nerve atrophy and optic neuritis. Small Russian eye studies report better vision when Semax was added to standard care; none used a placebo.

Tested in people 6

Studied in people, whatever the result: some worked, many didn’t or are unproven.

SS-31Approved drug: TrialDry macular degeneration (eye). Unproven: in a 48-week trial of 176 adults, it missed both main goals, vision and atrophy growth, though scans suggested slower loss of light-sensing cells. A 313-person Phase 3 trial is under way.
EpithalonPreclinical: TrialEye disease (retinitis pigmentosa). Unproven: a 2002 report says injections beside the eye helped 90% of patients with this inherited retinal disease, without numbers or a described control group. A US orphan designation was withdrawn in 2016.
CarnosineHuman studies: TrialCataracts (as N-acetylcarnosine eye drops). Unproven: a 2017 Cochrane review found no convincing evidence that N-acetylcarnosine drops, a related compound, reverse or slow cataracts; its two trials (114 people) couldn’t be reliably assessed.
ARA-290Human studies: TrialDiabetic macular edema (retinal swelling). Negative: in 9 people given 4 mg daily for 12 weeks, with no control group, vision and retinal thickness didn’t improve on average.
Thymosin Beta-4Human studies: TrialNon-healing corneal sores (neurotrophic keratopathy). Unproven: in an 18-person Phase 3 trial, eye drops healed sores in 6 of 10 vs 1 of 8 on placebo by day 29, short of significance; the gap was significant by day 43.
Thymosin Beta-4Human studies: TrialDry eye. Negative: in two Phase 3 trials of about 1,300 people (ARISE-2 and ARISE-3), eye drops improved corneal staining and eye discomfort no more than placebo.

Seen only in animals 1

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

P21Preclinical: AnimalAge-related macular degeneration. Unproven: in old rats treated for 3 months and Alzheimer’s-model mice treated for 18 months, it reduced retinal changes resembling macular degeneration. No human data.

Kidneys and bladder 18

On a label 3

Approved uses, from a product label somewhere in the world.

SemaglutideApproved drug: LabelKidney disease in type 2 diabetes. Ozempic is approved to lower the risk of kidney decline, kidney failure and heart death. In FLOW, these events hit 18.7% vs 23.2% on placebo over a median 3.4 years.
L-CarnitineApproved drug: LabelCarnitine deficiency on dialysis. Approved (IV). It raises blood carnitine, but the label says effects on symptoms and outcomes haven’t been determined; a 2022 Cochrane review (52 trials) found little or no effect on fatigue or cramps.
DesmopressinApproved drug: LabelNocturia from nighttime overproduction of urine. Nocdurna and Noctiva were FDA-approved but are discontinued in the US (Noqdirna is sold in the UK). In 3-month trials, nighttime trips fell 0.3–0.4 more than with placebo.

Tested in people 6

Studied in people, whatever the result: some worked, many didn’t or are unproven.

DulaglutideApproved drug: TrialKidney disease in type 2 diabetes. Not an approved use: in an exploratory REWIND analysis, heavy urine protein, a 30% kidney-function drop or dialysis hit 17.1% vs 19.6% on placebo, mostly through fewer urine-protein cases.
BPC-157Preclinical: TrialBladder pain (interstitial cystitis). Unproven: 10 of 12 women reported full relief after one 10 mg treatment injected into the bladder wall during a scope procedure. No placebo group; one clinic.
OctreotideApproved drug: TrialPolycystic kidney disease. Mixed, not approved: in two Italian trials (79 and 100 adults), the monthly depot slowed kidney growth at 1 year; in the larger one, kidney function didn’t decline significantly slower over 3 years.
DesmopressinApproved drug: TrialPreventing too-fast sodium correction. Hospital use under study: a French phase 3 trial (DASSOH, 260 adults) is testing routine desmopressin to stop sodium rising too fast in severe hyponatremia.
PalopegteriparatideApproved drug: TrialProtecting kidney function. Promising, unproven: in a post hoc look at PaTHway, eGFR, a kidney filtering measure, rose 9.0 points by 2 years with no comparison group, and urine calcium stayed normal.
CetrorelixApproved drug: TrialEnlarged prostate (BPH). Negative: a long-acting injection improved symptom scores in a phase 2 trial, but two 52-week placebo-controlled phase 3 trials in about 1,090 men found no difference. Never approved for this.

Seen only in animals 6

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

SLU-PP-332Preclinical: AnimalKidney aging. Unproven in people: aged mice treated for 8 weeks had less protein in their urine, a sign of kidney strain, and less kidney inflammation.
FOXO4-DRIPreclinical: AnimalKidney function in aging. Unproven in people: in fast-aging and naturally old mice, it lowered blood urea and creatinine, markers that rise as kidney filtering declines, 30 days after treatment.
CartalaxPreclinical: AnimalKidney aging. Unproven in people: in kidney cell and tissue cultures, including tissue from old rats, it boosted cell renewal and lowered aging markers such as p16 and p53.
OvagenPreclinical: AnimalAcute kidney injury. In rats with kidney injury from cisplatin, gentamicin or cut-off blood flow (2015 and 2017 studies by the developers and a Ukrainian partner lab), it limited the loss of kidney function. Not tested in people.
OvagenPreclinical: AnimalKidney aging. In developer studies (2014–2018) of kidney cell and tissue cultures, including old-rat tissue, it raised cell renewal and lowered aging markers; in old rats it increased urine output. Unproven in people.
ProstamaxPreclinical: AnimalProstate tissue renewal. Unproven in people: in tissue cultures from young and old rats, a tiny concentration (0.05 ng/mL) stimulated prostate tissue growth, as related peptides did in their own tissues (Zakutskii 2006).

Claims without data 3

Promoted by sellers, clinics or users, with no study behind the claim.

ProstamaxPreclinical: No studyChronic prostatitis. Unproven: no study has tested Prostamax in men or animals with prostatitis. Russian prostatitis trials used cattle prostate extracts (Prostatilen, Vitaprost), a different product.
ProstamaxPreclinical: No studyEnlarged prostate (BPH). Unproven: no published study has tested it for an enlarged prostate or urine flow, in people or animals.
TestagenPreclinical: No studyChronic prostatitis. Some guides cite a prostatitis study showing a testosterone rise, but no such study of this peptide appears in PubMed.

Lungs and breathing 11

Tested in people 3

Studied in people, whatever the result: some worked, many didn’t or are unproven.

VIPApproved drug: TrialCOVID-19 respiratory failure. Not shown: IV aviptadil missed its main goal in trials of 196 and 461 people; in the larger, 90-day deaths were 38% vs 36% on placebo. An 80-person inhaled trial reported faster discharge.
VIPApproved drug: TrialSarcoidosis and lung inflammation. Unproven: in a 20-person open-label study, 4 weeks of inhaled VIP was well tolerated and lowered an inflammatory signal (TNF-alpha) from lung immune cells. No placebo group.
VIPApproved drug: TrialPulmonary hypertension. Unproven: inhaled VIP lowered lung artery pressure in 8 patients (2003), and one dose had a small, brief effect in 20 others (2008). No placebo-controlled trial has been published.

Seen only in animals 5

Results in animals or cells only. Most treatments tested in animals never reach approval for people.

FOXO4-DRIPreclinical: AnimalLung scarring (pulmonary fibrosis). Unproven in people: in mice with lung scarring caused by the drug bleomycin or by radiation, it reduced collagen buildup and tissue damage.
BronchogenPreclinical: AnimalBronchitis and COPD. Unproven in people: in rats with COPD-like damage from nitrogen dioxide, a month of treatment reduced airway remodeling, emphysema and inflammation (Kuzubova 2015). No human study has been published.
BronchogenPreclinical: AnimalPneumonia and lung injury. Unproven: its developers say it helped animal models of bacterial lung inflammation, fibrosis and toxic lung damage, in studies not found in PubMed. No human data.
BronchogenPreclinical: AnimalLung and airway aging. Unproven: in aging cultures of human embryonic bronchial cells it raised cell-renewal markers and airway-lining genes (Khavinson 2014). It hasn’t been tested in older people or smokers.
ThymulinHuman studies: AnimalAsthma and airway scarring. Unproven in people: in mice with allergic asthma, gene therapy that made thymulin inside the lungs reduced airway inflammation and remodeling.

Claims without data 3

Promoted by sellers, clinics or users, with no study behind the claim.

ChonlutenPreclinical: No studyBronchitis and COPD. Unproven: sold for the bronchi and lungs, but no animal or human study of Chonluten in any lung disease has been published.
ChonlutenPreclinical: No studyRecovery after COVID-19 or pneumonia. Some guides promote it after COVID-19, but no study has tested it for COVID-19, pneumonia or recovery from either.
BronchogenPreclinical: No studyAsthma. Unproven: no study has tested it in asthma, in people or animals.

Sources: each answer comes from the compound’s own page, where its sources are listed; Ineichen et al., animal-to-human translation (PLoS Biol 2024), PMID 38870090.

By Vial Guide editorsLast reviewed October 7, 2026

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