Can peptides cause hair loss?

Each answer says whether hair loss was reported, and how often where that’s known. “Not reported” means the label or trials didn’t list it, not that it can’t happen. Talk to a doctor or pharmacist about any symptom that worries you.

From a product label 7

What the prescribing information says, with rates against placebo where the label gives them.

ExenatideApproved drug

LabelHair loss appears among reports after approval, so how often it happens is unknown. It wasn’t among the common side effects in the trials.

LiraglutideApproved drug

LabelHair loss is listed among reports after approval for both Victoza and Saxenda, so how often it happens isn’t known. It wasn’t among the common side effects in the trials.

OrforglipronApproved drug

LabelHair loss: 4–5% vs 2% on placebo, mostly in women (7% vs 3%; men 0.9% vs 0.7%). The label links it to weight loss.

SemaglutideApproved drug

LabelHair loss: 3% vs 1% on placebo at 2.4 mg and 6% at 7.2 mg, mostly in women. The label links it to weight loss.

TirzepatideApproved drug

LabelHair loss: 4–5% vs 1% on placebo, mostly in women (7.1% vs 0.5% of men). The label links it to weight loss; no one stopped tirzepatide for it.

TriptorelinApproved drug

LabelHair loss is uncommon (under 1 in 100) in men and women, per the UK label. It isn’t listed in the US labels.

Melanotan 1Approved drug

LabelHair loss isn’t a listed side effect. The EU label lists hair color changes as uncommon (under 1 in 100).

From human studies 2

What published trials and case reports found.

SurvodutideHuman studies

TrialHair loss: 5 of 214 (2.3%) on survodutide vs none of 79 on placebo in the 48-week MASH phase 2 trial, 4 of them at 6.0 mg.

GlutathioneApproved drug

TrialNot listed in the Italian label. In a 151-patient cisplatin trial, hair-loss scores were better with glutathione than without.

A precaution, not measured 3

A concern that follows from how it works or from a related drug.

hCGApproved drug

PrecautionNot listed in the labels. In men it raises testosterone, which could speed inherited hair thinning in those prone to it.

IGF-1 DESPreclinical

PrecautionNo human data for DES. Hair loss and changes in hair texture have been reported with mecasermin since approval.

IGF-1 LR3Preclinical

PrecautionNo human data for LR3. Hair loss and changes in hair texture have been reported with mecasermin since approval.

Seen only in animals 1

Animal findings don’t show what happens in people.

FOXO4-DRIPreclinical

AnimalNo human data. In fast-aging and very old mice, thinning fur grew denser rather than falling out.

Studied in people, not reported 37

Labels or trials covered enough people and didn’t report it. It can still happen.

CerebrolysinApproved drug

Not reportedNot listed in the EU or Russian labels. In a Cochrane review of stroke trials (1,607 people), overall side effects were as common as on placebo.

DSIPApproved drug

Not reportedNot listed in the Deltaran label or reported in the small IV studies (single doses to about 3 weeks of injections).

GHRP-2Approved drug

Not reportedNot listed in the Japanese label, based on single test doses in 227 trial participants; studies of repeated use gave few safety details.

GonadorelinApproved drug

Not reportedNot listed in the UK label, which covers a single diagnostic dose.

L-CarnitineApproved drug

Not reportedHair loss isn’t listed in the label, whose dialysis trials reported events seen in 5% or more of 130 people on IV levocarnitine.

MazdutideApproved drug

Not reportedHair loss wasn’t among side effects reported in 5% or more of 177 adults in the 56-week US phase 2 trial; Chinese trial reports don’t mention it.

OxytocinApproved drug

Not reportedNot reported in nasal trials, including 24 weeks of daily use in 290 children and teens, or listed in the labor drug’s label.

PT-141Approved drug

Not reportedNot listed in the label, whose controlled trials followed 627 women on it for 24 weeks, with a 52-week extension.

SelankApproved drug

Not reportedNot listed in the Russian label or reported in the small Russian trials of 60–70 patients each.

SemaxApproved drug

Not reportedNot listed in the Russian labels or reported in the small Russian trials (27–187 patients, mostly 10-day courses).

SS-31Approved drug

Not reportedNot a listed side effect, and not reported by 5% or more of 117 adults over 48 weeks, or by 2 or more of 30 in a 4-week trial.

TesamorelinApproved drug

Not reportedHair loss isn’t listed in the label’s trials, in which 740 people with HIV took tesamorelin for up to 52 weeks.

ThymalinApproved drug

Not reportedNot listed in the Russian label, which names only allergic reactions; published trials, mostly small and from Russia, gave few safety details.

Thymosin Alpha-1Approved drug

Not reportedNot listed in either label; the Indonesian label cites use in over 2,000 people, with drug-related side effects in under 1%.

VIPApproved drug

Not reportedNot listed in Invicorp’s label. In a 196-person trial of 3-day IV infusions, no side effect type except diarrhea was more common than on placebo.

AOD9604Human studies

Not reportedNot listed among the side effects in trials of 893 adults lasting up to 24 weeks.

ARA-290Human studies

Not reportedNot reported in the trials, which treated about 120 people for 28 days to 12 weeks.

ArgirelineHuman studies

Not reportedNot reported in the small skin trials (up to 60 people, mostly 4–8 weeks); the most reliable lab tests found almost none reaches deeper skin.

CagrilintideHuman studies

Not reportedNot among common side effects (5% or more) in the 26-week trial, which gave cagrilintide alone to 506 people.

CJC-1295 with DACHuman studies

Not reportedNot among the side effects FDA summarized from the published trials (63 healthy adults, up to 49 days).

GHK-CuHuman studies

Not reportedHair loss wasn’t reported in the small topical studies (13–86 people, mostly 8–12 weeks). It’s promoted for hair growth; injection hasn’t been studied in people.

GHRP-6Human studies

Not reportedNot reported in single-dose studies or 24-hour infusions in healthy men. Repeated daily use hasn’t been studied.

HexarelinHuman studies

Not reportedNot reported: 60 children and young people had no side effects after one IV dose, and studies of up to 16 weeks gave few safety details.

IpamorelinHuman studies

Not reportedNot among the side effects reported from the IV studies (40 healthy men, one dose; 56 surgery patients, up to 7 days).

Kisspeptin-10Human studies

Not reportedNot reported in small, short human studies (about 300 people, single doses to 12 days), which often didn’t track side effects.

LarazotideHuman studies

Not reportedNot more common than on placebo in a pooled analysis of four trials (626 people with celiac disease, up to 12 weeks).

LL-37Human studies

Not reportedNot among the side effects reported in the ulcer trials (about 200 people, up to 13 weeks), which applied it to wounds.

MatrixylHuman studies

Not reportedNot reported in the skin trials (93 women for 12 weeks; 196 using a mix for 8 weeks), where it was well tolerated.

Melanotan 2Human studies

Not reportedHair loss wasn’t reported in the three small trials (23 men, single doses to 2 weeks), which gave few safety details.

MK-677Human studies

Not reportedNot reported as a side effect in trials of up to 2 years (65 older adults) or 12 months (563 people with Alzheimer’s disease).

NAD+Human studies

Not reportedNot reported in the small human studies of injected NAD+ or NADH, which gave few safety details.

RetatrutideHuman studies

Not reportedHair loss wasn’t among side effects reported in 5% or more of 338 adults in the 48-week phase 2 trial. Phase 3 rates weren’t given in published abstracts.

SermorelinHuman studies

Not reportedHair loss wasn’t listed among side effects in the Geref trials (350 patients, mostly children, most treated for up to a year).

SNAP-8Human studies

Not reportedNot reported in two small patch studies that mixed it with other actives (24 people for 28 days; another for 12 weeks); SNAP-8 alone hasn’t been studied.

TesofensineHuman studies

Not reportedNot listed among common side effects in published trials, the largest lasting 24 weeks.

Thymosin Beta-4Human studies

Not reportedNot reported in trials of over 1,000 people using eye drops, gel or IV infusions for up to 12 weeks.

BPC-157Preclinical

Not reportedNot reported in the small human studies (about 80 people, one dose to 2 weeks of use), which gave few safety details.

No human safety data 18

No one has been given it in a published study, so it can’t be ruled in or out.

DihexaHuman studies

No dataNo human data for dihexa itself. It wasn’t among side effects seen in 4% or more of people taking its injected prodrug for 26 weeks.

5-Amino-1MQPreclinical

No dataNo human safety data: no published study has given it to a person.

AdamaxPreclinical

No dataNo human or animal safety data; Adamax has never been studied.

AHK-CuPreclinical

No dataNo human data. It’s promoted for hair growth, but no study has checked whether it causes or prevents shedding in people.

CartalaxPreclinical

No dataNo human data: no study of cartalax in people has been published, so side effects are unknown.

CJC-1295 (no DAC)Preclinical

No dataNo human safety data for this peptide.

EpithalonPreclinical

No dataNo human safety data: FDA found no study that assessed safety, and its one placebo-controlled trial (40 women, 20-day spray) didn’t report side effects.

Follistatin-344Preclinical

No dataNo human data for injected follistatin; hair loss wasn’t reported in the muscle gene-therapy trials.

HGH Fragment 176-191Preclinical

No dataNo human safety data for this peptide.

HumaninPreclinical

No dataNo human data: no one has been given humanin or its stronger version HNG in a published study, so side effects are unknown.

KPVPreclinical

No dataNo human safety data: FDA’s 2026 review found no study and no adverse-event report for KPV by any route.

MGFPreclinical

No dataNo human safety data: no published study has given MGF to a person.

MOTS-cPreclinical

No dataNo human safety data for MOTS-c itself. In a 4-week trial of a modified version, CB4211, injection-site reactions were the only side effect in over 10% of the 11 treated.

PE-22-28Preclinical

No dataNo human data: PE-22-28 has never been given to a person in a study.

PEG-MGFPreclinical

No dataNo human safety data: FDA found no human exposure data for PEG-MGF by any route.

PinealonPreclinical

No dataNo useful human safety data: the few small Russian reports on pinealon gave no details of side effects.

SLU-PP-332Preclinical

No dataNo human safety data: no published study has given it to a person.

TB-500Preclinical

No dataNo human safety data: FDA found no study that has given TB-500 to a person.

Sources

Each answer comes from the compound’s own page, under “Can it cause …?”, where its sources are listed.