Peptides

Melanotan II: what the evidence and the law actually say about the "tanning injection"

By the US Health Digest editorial team · Published August 18, 2026 · Every claim linked to its primary source

Melanotan II is a synthetic analogue of α-melanocyte-stimulating hormone (α-MSH) — a non-selective melanocortin receptor agonist — sold online as an injection or nasal spray for tanning, and no FDA-approved drug product contains it. In an April 1, 2020 warning letter naming Melanotan II, FDA said it is "not the subject of an applicable USP or NF monograph," is "not a component of an FDA-approved human drug," and does "not appear on the 503A bulks list." The published human evidence for tanning is a 1996 placebo-controlled pilot in three men; almost everything since is case reports. Two different melanocortin peptides do hold FDA approvals — afamelanotide and bremelanotide — and neither is this. We publish no dosing, vendors or sourcing.

What melanotan II is, and the two peptides it is not

Melanotan II is a lactam-bridged cyclic heptapeptide built from the core of α-MSH, first described in a University of Arizona pilot phase 1 study in 1996. Because it activates melanocortin receptors non-selectively — not just the MC1 receptor that drives pigmentation — its pharmacology is not confined to skin, which is why the same molecule was studied as an erection-inducing drug. One of those relatives is closer than the word "different" suggests: bremelanotide, approved as Vyleesi, is melanotan II's major active metabolite, which is precisely why the tanning peptide produces erections and, in the case reports below, priapism. Nearly every confusion here comes from collapsing three molecules into one word; a result for one does not transfer to another, the rule governing every peptide claim.

The US legal position, precisely

Searched through the openFDA API on August 18, 2026, Drugs@FDA and FDA's structured product-labeling database return no match for "melanotan" or "melanotan II" — no approved application, no approved label, any route. The 2020 warning letter above says the same, listing Melanotan II among substances whose compounded products "are not eligible for the exemptions provided by section 503A(a)."

Nor is compounding a route in. FDA's page on bulk substances that "may present significant safety risks," updated April 22, 2026, lists Melanotan II under withdrawn nominations with FDA's assessment attached: it "may pose risk for immunogenicity for certain routes of administration due to the potential for aggregation or peptide-related impurities," and "published case reports discuss serious adverse events including melanoma, posterior reversible encephalopathy syndrome, sympathomimetic toxidrome and priapism" — the posture FDA also takes toward BPC-157 and GHK-Cu.

Enforcement is not hypothetical. In a 2016 notice of opportunity for hearing, FDA recounted warning a Tennessee company repeatedly through 2007 that its injectable tanning product "constituted a new drug under the FDCA that could not be introduced or delivered for introduction into interstate commerce without an FDA approved application," and moved to debar an individual involved. FDA's enforcement database also records three Class II recalls of compounded melanotan products — Florida 2018 and Texas 2022 for melanotan II, Kentucky 2022 for melanotan I — every one for "lack of sterility assurance."

What other regulators say

Australia's TGA is blunt: melanotan products, in any form, are "not approved for sale or use as a tanning agent in Australia" and "haven't been assessed for their quality or safety." On August 17, 2026 it reported testing seized nasal sprays labelled "30 MG": estimated content across the five bottles "ranged between 22 mg and 54 mg of Melanotan II based on the labelled volume of 20 mL per bottle."

The UK's MHRA, answering a freedom-of-information request on April 17, 2024, said unauthorised melanotan II products' "contents are unknown and there are no safeguards that these products meet our standards for quality, safety or effectiveness," and that "our advice to those who have used Melanotan II injections or nasal sprays is to stop using them immediately." It counted 16 UK suspected adverse-reaction reports from 2012 to 2022, cautioning that a report does not mean the product caused the event. An earlier reply names the loophole nasal sprays exploit: "where no medicinal claims are made, nasal tanning sprays containing melanotan II will not generally be regulated as medicinal products."

The human evidence for tanning, in full

PubMed, searched August 18, 2026 for "melanotan II" restricted to clinical-trial and randomized-controlled-trial publication types, returns four human trials of melanotan II. (A fifth hit is a retracted metallothionein paper that matches only on the abbreviation "MT-II"; it is excluded.) One concerns pigmentation; the other three concern erections.

The pigmentation study is Dorr 1996: a single-blind, alternating-day, placebo-controlled pilot phase 1 trial in three male volunteers over two weeks, in which "two subjects had increased pigmentation in the face, upper body and buttock." Three men, thirty years ago — that is the controlled human tanning evidence base. The erectile-dysfunction work is better designed: a double-blind placebo-controlled crossover in 10 men with psychogenic ED and a second crossover in 10 men with organic ED, later pooled by the same group as a supplement review of those 20 men — so the entire controlled ED corpus is about 20 participants, not 30. It says nothing about tanning, but it is the receptor pharmacology that makes the later priapism reports biologically plausible.

The peptide with actual tanning trials is the other one: Dorr 2004 alone reported three phase 1 studies of melanotan-1 (afamelanotide) enrolling 8, 12 and 8 subjects, and other melanotan-1 tanning studies followed, combining it with UV-B or sunlight — small and largely open-label, but published, and not melanotan II.

ClinicalTrials.gov, searched the same day, returned one melanotan II record: NCT07437560, a randomized, quadruple-masked phase 2 trial of 60 planned participants at one hospital in China, testing it alongside narrowband UV-B phototherapy for vitiligo — not tanning. It is recruiting, posted February 27, 2026, with no results, and its own summary calls it "an example interventional study record," so we treat it as a registration, not evidence. We found no trial testing whether melanotan II prevents sunburn or skin cancer.

The safety literature is case reports — and case reports have no denominator

Read this section for what it is: every study below describes one person, or a handful. A case report can establish that an event followed an exposure in an individual. It cannot establish causation, or incidence, because nobody knows how many people use melanotan II. There is no denominator.

Skin. Reports describe new and darkening moles: eruptive melanocytic naevi (2009), atypical melanocytic naevi (2013), eruptive and darkening naevi 24 hours after a single injection (2014). A systematic review compiled 93 articles covering 179 patients, attributing 41% of cases to immunosuppressive agents, chemotherapy or melanotan combined.

Melanoma. Reports include melanotan-associated melanoma (2011), melanoma in situ (2012), melanoma in a 20-year-old woman three months after self-injections (2014), oral mucosal melanoma in a 22-year-old woman who used a nasal spray (2025), and five primary melanomas in situ in one patient (2026). Several of these reports also describe sunbed or tanning-bed use alongside the drug, so co-exposure confounds them — and the reports do not consistently record it. A 2017 review put it correctly: "conclusive evidence linking these phenomena is lacking."

Systemic. Individual reports describe rhabdomyolysis with sympathomimetic toxicity and renal dysfunction (2012, one man, peak CPK 17,773 IU/L), posterior reversible encephalopathy syndrome (2013), renal infarction (2020), and priapism (2019; 2021, needing surgical decompression). A 2026 PRISMA review of 68 studies on tanning agents summarised it: "unregulated melanotan I and II use has caused serious adverse effects, including rhabdomyolysis, renal infarction, and priapism."

What is actually in the vial

Three laboratory analyses have measured gray-market melanotan II; none found the label accurate. In a 2015 study of vials bought from three online shops, they held 4.32 to 8.84 mg against a claimed 10 mg, with unknown impurities of 4.1–5.9% in two shops' vials. A 2024 forensic analysis of two vials submitted to a hospital toxicology laboratory measured purity at 30%. The TGA's 2026 nasal-spray testing found nearly a 2.5-fold spread across five bottles. Add the two US sterility recalls of compounded melanotan II above (the third covered melanotan I), and what a 2013 Public Health England survey of 395 men injecting image- and performance-enhancing drugs found: one in ten had been exposed to HIV, hepatitis B or hepatitis C. A vendor's certificate of analysis does not close that gap — see our guide to certificates of analysis.

The counterintuitive part

Melanotan II is marketed as a way to avoid sun damage — yet the documented harms are dermatological, and even the approved melanocortin agonist is treated as a pigment-surveillance risk. The Scenesse label warns it "may lead to generalized increased skin pigmentation and darkening of pre-existing nevi and ephelides," and instructs that "a full body skin examination (twice yearly) is recommended." That is the monitoring attached to a product a regulator has actually assessed; no comparable guidance exists for an unlabelled online vial, because no regulator has ever assessed one. Nor is a darker tone photoprotection: "No tan, fake or real, will protect skin against damage from sun exposure," the TGA states — and a study of 623 user-forum entries found sunbed use running alongside the drug, the exposure it supposedly replaces.

What a dermatologist can actually offer

At the category level, without brands:

• Topical sunless tanners containing DHA. Dihydroxyacetone is an FDA-approved color additive, restricted to products "applied only to external parts of the body and not to the lips or any body surface covered by mucous membrane," and not approved for inhalation or the eye area. It changes color, not risk: products without sunscreen must warn they do "not protect against sunburn."
• Photoprotection, which has randomized evidence. In the Nambour trial, 1,621 Queensland residents randomized to daily versus discretionary sunscreen had 11 versus 22 new primary melanomas through 2006 (HR 0.50; 95% CI 0.24–1.02), and 3 versus 11 invasive melanomas (HR 0.27; 95% CI 0.08–0.97).
• Mole checks, framed honestly. New or changing moles are a reason to be examined. For routine screening of people with no symptoms or history, the USPSTF concluded on April 18, 2023 that "the current evidence is insufficient to assess the balance of benefits and harms of visual skin examination by a clinician" (Grade I).

How to read the marketing

The FTC's Health Products Compliance Guidance sets the standard sellers are held to: "randomized, controlled human clinical trials (RCTs) are the most reliable form of evidence and are generally the type of substantiation that experts would require for health benefit claims" — and advertisers must hold it before the ad runs. A claim that a tanning peptide is safe, or shields skin from sun damage, needs such trials. They are not in the published record, and a "research use only" label does not supply them.

Questions for a clinician

• I have used a tanning peptide. Should I have a full-body skin examination, and how often?
• Have any moles changed in size, shape, border or color, and do any need biopsy?
• I self-injected. Should I be tested for hepatitis B, hepatitis C and HIV?
• Does a family history of melanoma or dysplastic naevi change your advice?
• What sun-protection and cosmetic-tanning options fit my skin type?

We publish no doses, sources or preparation instructions for melanotan II, and nothing here should be read as telling anyone how to use it.

Sources

1. FDA. Warning letter to Tailor Made Compounding LLC, 594743, April 1, 2020 — names Melanotan II among bulk substances that are "not the subject of an applicable USP or NF monograph," "not a component of an FDA-approved human drug," and do "not appear on the 503A bulks list." Link.
2. FDA. Certain Bulk Drug Substances for Use in Compounding May Present Significant Safety Risks (updated April 22, 2026) — Melanotan II under nominations withdrawn, with FDA's immunogenicity and adverse-event assessment. Link.
3. FDA. Notice of Opportunity for Hearing (NOOH), Manookian, Edward, August 5, 2016 — 2007 warning letters over an injectable tanning product as an unapproved new drug. Link.
4. FDA. SCENESSE (afamelanotide) approval letter, October 8, 2019, NDA 210797. Link. Prescribing information, including the nevus-darkening warning and twice-yearly skin examination. Link.
5. FDA. Drugs@FDA overview, VYLEESI (bremelanotide), NDA 210557, approved June 21, 2019. Link. Prescribing information. Link.
6. FDA. Drugs@FDA search interface — searched for "melanotan" and "melanotan II" via the openFDA API on August 18, 2026; no approved application or approved label returned. Link. FDA drug enforcement (recall) records for melanotan products, three Class II recalls for lack of sterility assurance. Link.
7. FDA. Sunless Tanners & Bronzers — DHA color-additive status and restrictions. Link.
8. TGA (Australia). Melanotan II tanning peptide products found to be inconsistently dosed, safety advisory published 17 August 2026 — 22 mg to 54 mg across five bottles labelled 30 mg. Link.
9. TGA (Australia). Don't risk using tanning products containing melanotan, 24 January 2025. Link.
10. MHRA (UK). FOI 24/274, 17 April 2024 — advice to stop using melanotan II immediately; 16 Yellow Card reports 2012–2022. Link.
11. MHRA (UK). FOI 21/1237, 20 December 2021 — nasal tanning sprays generally not regulated as medicinal products absent medicinal claims. Link.
12. Dorr RT, et al. Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study. Life Sci. 1996 — placebo-controlled pilot, 3 male volunteers. PMID 8637402.
13. Wessells H, et al. Synthetic melanotropic peptide initiates erections in men with psychogenic erectile dysfunction. J Urol. 1998 — double-blind placebo-controlled crossover, n=10. PMID 9679884.
14. Wessells H, Gralnek D, Dorr R, Hruby VJ, Hadley ME, Levine N. Effect of an alpha-melanocyte stimulating hormone analog on penile erection and sexual desire in men with organic erectile dysfunction. Urology. 2000;56(4):641–646. PubMed 11018622.
15. Wessells H, et al. Melanocortin receptor agonists, penile erection, and sexual motivation: human studies with Melanotan II. Int J Impot Res. 2000 — n=20, double-blind placebo-controlled crossover. PMID 11035391.
16. Dorr RT, et al. Effects of a superpotent melanotropic peptide in combination with solar UV radiation on tanning of the skin in human volunteers. Arch Dermatol. 2004 — three phase 1 studies of melanotan-1 (n=8, 12, 8). PMID 15262693.
17. ClinicalTrials.gov. NCT07437560 — phase 2, melanotan II as an adjunct to NB-UVB in stable nonsegmental vitiligo; recruiting, no results. Link.
18. Habbema L, et al. Risks of unregulated use of alpha-melanocyte-stimulating hormone analogues: a review. Int J Dermatol. 2017. PMID 28266027.
19. Burian EA, Jemec GBE. Eruptive Melanocytic Nevi: A Review. Am J Clin Dermatol. 2019 — 93 articles, 179 patients. PMID 31119650.
20. Resnick G, et al. Insights into Tanning Biology and Tanning Products. J Clin Aesthet Dermatol. 2026 — PRISMA systematic review, 68 studies. PMID 41890775.
21. Case reports of melanocytic change and melanoma: PMID 19575725 (2009); PMID 21564053 (2011); PMID 22724573 (2012); PMID 23914578 (2013); PMID 24334249 (2014); PMID 24355990 (2014); PMID 40210573 (2025); PMID 42328529 (2026).
22. Case reports of systemic events: rhabdomyolysis PMID 23121206; posterior reversible encephalopathy syndrome PMID 23648958; priapism PMID 30796078 and PMID 33460908; renal infarction PMID 31953620.
23. Breindahl T, et al. Identification and characterization by LC-UV-MS/MS of melanotan II skin-tanning products sold illegally on the Internet. Drug Test Anal. 2015 — 4.32–8.84 mg against a claimed 10 mg; impurities 4.1–5.9%. PMID 24771717.
24. Deville M, Charlier C. Barbie drug identification: Not a child's play. J Forensic Sci. 2024 — seized vials, purity 30%. PMID 39302005.
25. Gilhooley E, et al. Melanotan II User Experience: A Qualitative Study of Online Discussion Forums. Dermatology. 2021 — 623 entries, 205 participants. PMID 34464955.
26. Public Health England. Steroid users at risk of HIV, hepatitis B and hepatitis C, 13 September 2013 — 395 men surveyed; 1 in 10 exposed to one or more of HIV, hepatitis B or hepatitis C. Link.
27. Green AC, et al. Reduced melanoma after regular sunscreen use: randomized trial follow-up. J Clin Oncol. 2011 — 1,621 randomized. PMID 21135266.
28. US Preventive Services Task Force. Skin Cancer: Screening, April 18, 2023 — Grade I statement. Link.
29. Federal Trade Commission. Health Products Compliance Guidance. Link.