Can peptides cause acne, rashes or skin changes?

Each answer says whether acne, rashes or skin changes 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 21

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

CerebrolysinApproved drug

LabelUncommon: itching and inflamed skin (EU label). Injecting too fast can cause warmth and sweating (0.9% vs 0.8% on placebo); injection-site redness and burning also occur.

DSIPApproved drug

LabelThe Deltaran label lists possible allergic reactions (frequency not given) and rules it out in people allergic to it.

ExenatideApproved drug

LabelExcess sweating 3% vs 1% on placebo; itching, hives and rash were reported after approval. The discontinued weekly form caused injection-site lumps in about 1 in 10 users.

GHRP-2Approved drug

LabelA hot feeling is the most common reaction (16.0%); sweating (0.1–5%) and facial flushing (frequency not known) are also listed. Rash and acne aren’t.

GlutathioneApproved drug

LabelThe label lists very rare rashes after muscle injection, which cleared on stopping, and soreness at the injection site. Skin lightening is why many people use it.

GonadorelinApproved drug

LabelItching and swelling are uncommon (under 1 in 100); hives and redness are rare. With pumps, allergic redness at the infusion site was the main side effect in small studies.

L-CarnitineApproved drug

LabelInjection-site reactions: 33% vs 59% on placebo; rash 3% vs 3%. The label lists body odor, and serious rash, hives and face swelling with oral forms.

LiraglutideApproved drug

LabelInjection-site reactions (redness, itching, rash) 13.9% vs 10.5% on placebo with Saxenda. Reports after approval include burning or tingling skin and skin protein deposits (cutaneous amyloidosis).

Melanotan 1Approved drug

LabelSkin darkening 4% vs 0% and moles (nevi) 4% vs 2%; implant-site reactions 21% vs 10% (US label). Labels advise a full-body skin exam twice a year.

OrforglipronApproved drug

LabelBurning or tingling skin (dysesthesia): 1% at 17.2 mg vs 0.1% on placebo. Allergic reactions 0.5% vs 0.3%. As a pill, it causes no injection-site reactions.

PT-141Approved drug

LabelFlushing 20.3% vs 0.3% on placebo. Dark patches on the face, gums or breasts: 1% at up to 8 doses a month, 38% after 8 daily doses; some didn’t fade.

SelankApproved drug

LabelThe Russian label lists allergic reactions, including delayed ones (frequency not given), and warns that the drops’ paraben preservative can cause them.

SemaglutideApproved drug

LabelBurning, tingling or sensitive skin (dysesthesia): 22% at 7.2 mg vs 6% at 2.4 mg. Injection-site reactions 1.4% vs 1%; rash and hives 3% each in teens, vs 0%.

SS-31Approved drug

LabelInjection-site redness 100% vs 25% on placebo, itching and hardening 67% vs 17%, hives at the site 25% vs 0%. Rash or eczema-like skin reactions can signal allergy.

TesamorelinApproved drug

LabelInjection-site reactions (redness, itching, pain): 25% vs 14% on placebo. Rash 4% vs 2%. Allergic reactions such as itching, flushing or hives occurred in 4%.

ThymalinApproved drug

LabelAllergic reactions are the only side effect the Russian label lists, without rates. It advises caution in people with a history of allergies.

Thymosin Alpha-1Approved drug

LabelItaly’s label lists only occasional mild, brief pain at the injection site. Indonesia’s adds rare redness and rash; local irritation and redness were the most common effects in trials.

TirzepatideApproved drug

LabelInjection-site reactions 6–8% vs 2% on placebo. Allergic reactions 5% vs 3%, mostly rash or itching. Burning or tingling skin (dysesthesia) was rare: 0.2–0.4% vs 0.1%.

TriptorelinApproved drug

LabelRash 1.7% and itching 1.4% in US trials; acne is very common in women (UK label). Rare severe blistering skin reactions mean stopping it if confirmed.

VIPApproved drug

LabelFacial or body flushing is common with Invicorp; in one trial it followed 33.9% of injections. Bruising and small blood collections at the injection site are also common.

SermorelinHuman studies

LabelInjection-site pain, swelling or redness affected about 1 in 6 patients; 3 of 350 stopped because of it. Hives occurred in under 1%.

From human studies 19

What published trials and case reports found.

hCGApproved drug

TrialAcne affected 52% of men given hCG with FSH for 18 months in one trial. Labels list injection-site bruising, redness and itching, and allergic rashes or hives.

MazdutideApproved drug

TrialRash 3.1% and skin sensitivity 3.1% vs none on placebo in the US phase 2 trial. Injection-site reactions: 3.2% vs 6.5% on placebo in Chinese phase 2.

OxytocinApproved drug

TrialNasal spray: rash 11.0% vs 9.7% and acne 3.4% vs 8.3% on placebo over 24 weeks. With IV use, flushing, rash and allergic swelling are listed.

AOD9604Human studies

TrialIV studies logged single cases of infusion-site pain, bruising and reaction. Injections under the skin, today’s route, have never been studied, so site reactions there are unknown.

ARA-290Human studies

TrialSweating in 2 of 46 people, itch and rosacea in 1 each, vs a rash in 1 of 16 on placebo. Injection-site pain was commoner on placebo.

ArgirelineHuman studies

TrialEyelid irritation: 2 of 12 on peptide vs 2 of 12 on placebo in a trial; a 50-person patch test found no allergy. An injected case caused a skin infection.

CagrilintideHuman studies

TrialInjection-site redness 4–17% vs 0% on placebo, plus itching and rash at the site, in the 26-week trial; most common at 4.5 mg.

CJC-1295 with DACHuman studies

TrialInjection-site reactions (redness, hardening, pain, itching) hit about 70% in one trial and brief hives at the site nearly 30%; in another, everyone on the drug had them.

DihexaHuman studies

TrialIn the prodrug’s 26-week trial, injection-site reactions hit 57.1% vs 14.2% on placebo and itching 4.5% vs 1.8%. Dihexa in DMSO on the skin is unstudied.

Kisspeptin-10Human studies

TrialOne of 18 people in a 40-hour IV study had a skin infection. FDA warns injected peptides like it may provoke immune reactions, more so under the skin.

LL-37Human studies

TrialOn ulcers, dermatitis judged possibly related occurred in 1 of 97 in the largest trial. One of 3 melanoma patients injected with it developed wart-like growths that cleared after stopping.

MatrixylHuman studies

TrialA 51-person patch test found no allergy, and a 93-woman trial found it well tolerated. A cream mixing it with other actives caused more itch during radiotherapy.

Melanotan 2Human studies

TrialIt darkens skin and moles; case reports after melanotan injections describe crops of new moles and dark nail bands. Bremelanotide caused dark patches in 38% given 8 daily doses (label).

MK-677Human studies

TrialNight sweats and dry skin were reported in small studies, and one woman stopped for a rash in an osteoporosis trial. Acne wasn’t reported.

RetatrutideHuman studies

TrialSkin sensitivity or tingling (dysesthesia): 5.1% at 4 mg and 12.3–12.5% at 9–12 mg vs 0.9% on placebo in TRIUMPH-1; 4–7% vs 1% in TRIUMPH-2.

SurvodutideHuman studies

TrialRash 3.7% vs 3.8% and injection-site reactions 3.3% vs 6.3% on placebo in the MASH phase 2 trial, so neither stood out.

Thymosin Beta-4Human studies

TrialIn a leg-ulcer trial, itching hit 4 of 55 people on the gel vs 1 of 17 on placebo; redness 3 and rash 2 of 55, vs none.

MOTS-cPreclinical

TrialInjection-site reactions, short-lived and mostly mild to moderate, were the only side effect in over 10% of 11 adults on its modified version CB4211 for 4 weeks.

SNAP-8Human studies

TrialNo skin reactions were reported in two patch studies of mixes (24 people for 28 days; another for 12 weeks). Users report occasional redness or irritation.

From user reports 13

Commonly reported by people who use it, not established in a study.

GHK-CuHuman studies

CommunityUsers report stinging, redness, itch or bruising where they inject, and brief flushing or warmth afterward; skin products can sting. Topical studies gave few safety details; copper allergy is uncommon.

HexarelinHuman studies

CommunityUsers report flushing after doses. Skin effects weren’t reported in the small human studies, which gave few safety details.

IpamorelinHuman studies

CommunityUsers report redness or itching where they inject. No study has given it under the skin; FDA flagged a risk of immune reactions to injected peptides.

NAD+Human studies

CommunityStinging or burning at the injection site is the most common complaint, and flushing is also reported. No study has measured skin reactions.

5-Amino-1MQPreclinical

CommunityUsers of injectable forms report stinging at the injection site. No study has checked.

AHK-CuPreclinical

CommunityUsers report scalp itch, redness or irritation. No study has measured it; allergy to copper is uncommon but can occur.

BPC-157Preclinical

CommunityUsers report injection-site redness and itch. An FDA report describes darkened skin and gums after a BPC-157 and TB-500 mix; the darkening returned when the mix was restarted.

CJC-1295 (no DAC)Preclinical

CommunityUsers report redness or itching where they inject. With CJC-1295 with DAC, injection-site reactions hit about 70% of one trial, and brief hives at the site nearly 30%.

EpithalonPreclinical

CommunityUsers report mild redness at injection sites. No human study has reported skin effects; FDA flags immune reactions as a risk of injected peptides.

KPVPreclinical

CommunityUsers report redness or itch where they inject. Applied to cadaver skin, the peptide barely crossed the outer layer unless the skin was breached.

PE-22-28Preclinical

CommunityUsers report injection-site redness or soreness, and burning or dryness with nasal sprays. No human study has looked.

SLU-PP-332Preclinical

CommunityUsers report injection-site irritation or small lumps. No study has checked.

TB-500Preclinical

CommunityUsers report injection-site redness. FDA describes skin and gum darkening, which came back on restarting, in someone injecting a BPC-157 and TB-500 mix.

A precaution, not measured 6

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

HGH Fragment 176-191Preclinical

PrecautionUntested. Any injection can redden or irritate the skin, and FDA flagged a possible immune reaction risk for injected AOD9604, a related peptide.

AdamaxPreclinical

PrecautionNo safety data for Adamax. Redness, itching or infection at the injection site is possible with any injected peptide.

Follistatin-344Preclinical

PrecautionNo human data for injected follistatin. It is a protein grown in cells, so injection-site reactions and immune responses to it are possible.

IGF-1 DESPreclinical

PrecautionNo human data for DES. Mecasermin causes fat buildup at injection sites (lipohypertrophy), bruising, and local allergic reactions such as itching and hives; severe allergic reactions are rare.

IGF-1 LR3Preclinical

PrecautionNo human data for LR3. Mecasermin causes fat buildup at injection sites (lipohypertrophy), bruising, and local allergic reactions such as itching and hives; severe allergic reactions are rare.

PEG-MGFPreclinical

PrecautionNo human data. FDA flags a significant risk of immune reactions; 22–25% of healthy blood donors carry antibodies to PEG, which can blunt or cause reactions to pegylated drugs.

Studied in people, not reported 4

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

GHRP-6Human studies

Not reportedIn an 18-man study, facial flushing followed GHRH but not GHRP-6. No skin effects were reported in other single-dose studies.

SemaxApproved drug

Not reportedNot listed in the Russian labels or reported in trials. The labels rule it out with allergy to any ingredient; the drops contain a paraben preservative.

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).

TesofensineHuman studies

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

No human safety data 5

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

CartalaxPreclinical

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

FOXO4-DRIPreclinical

No dataNo human data: no one has been given FOXO4-DRI in a published study, so side effects are unknown.

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.

MGFPreclinical

No dataNo human safety data. Any injection can cause redness, swelling or pain at the site; a hot, spreading, painful site needs medical care.

PinealonPreclinical

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

Sources

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