Skin & aging Melanocortin agonist (MC1R/MC3R/MC4R)
Melanotan II
Regulatory status
Status at a glance
503A compounding status
Removed from Category 2 (review pending)
FDA has moved this substance out of Category 2 while it is reviewed further. Removal from Category 2 does not authorize compounding. Its status remains unsettled until FDA completes its evaluation.
- FDA approval
- Not FDA-approved for any use
- 503B outsourcing
- Not determined
- Anti-doping (WADA)
- Not on the WADA Prohibited List
- DEA schedule
- Not a controlled substance
About peptide status
Most peptides discussed here are not FDA-approved for any use, and products labeled “research use only” are not for human use. Removal from Category 2 does not authorize compounding. PCAC votes are non-binding recommendations; FDA and HHS make the final decisions.
This is not medical or legal advice, and we do not publish dosing, sourcing or reconstitution information. Talk with a licensed clinician before using any peptide.
If you think you are having a medical emergency, call 911.
Key takeaway
Melanotan II is a synthetic melanocortin peptide sold on the gray market for tanning and libido, and it is not FDA-approved. No controlled human trials support tanning or libido use. Its first human study, a 1996 pilot in three healthy men, found increased pigmentation in two of three and spontaneous erections lasting 1 to 5 hours. One of two men escalated to the highest dose had Grade II somnolence and fatigue. Published case reports add concerning skin changes.
At a glance
- FDA status
- Non-FDA-approved, unregulated product sold in the gray market
- What it is
- Non-selective melanocortin receptor agonist, marketed for tanning and libido
- Research
- No controlled human evidence for the marketed uses; case reports describe skin-lesion concerns
- Safety
- The FDA has issued warnings about injectable tanning products containing melanotan
- Evidence strength
- Low research
Summary
Melanotan II is a gray-market melanocortin peptide sold for tanning and libido. It is not FDA-approved, and no controlled trials support those uses.
What is Melanotan II?
Melanotan II is a synthetic cyclic peptide that activates several melanocortin receptors (MC1R, MC3R, MC4R, and MC5R), sometimes nicknamed "the Barbie drug." It is the structural parent from which the approved drug bremelanotide was derived. It is sold through gray-market channels as an injectable for tanning and sexual arousal, and it is not an approved medicine.
How does it work?
Melanotan II is proposed to work through two receptor effects: activating MC1R on skin cells to drive pigmentation and tanning, and activating MC4R in the brain, which is linked to sexual arousal and appetite. The sexual and appetite effects come largely from animal and early pharmacology work. This describes the proposed mechanism, separate from whether unregulated use for these purposes is effective or safe.
Is it FDA-approved?
Safety note
Status: Non-FDA-approved, unregulated product sold in the gray market
Category: Wellness and performance · Primary body area: Skin & aging
No. Melanotan II is not approved by the FDA and is an unapproved drug; the FDA has previously issued warning letters targeting injectable tanning products containing melanotan. Its compounding nomination was withdrawn, so FDA removed it from its Category 2 list in April 2026 and lists it as nominated but withdrawn. The approved melanocortin drugs Scenesse (for a rare light disorder) and Vyleesi (for low sexual desire in certain women) are distinct, regulated products that Melanotan II is not.
What does the research show?
Editor’s note
Evidence strength: Low research (2 human · 0 animal/cell studies)
There is no controlled human evidence for the marketed uses, and the published literature consists of case reports and clinician warnings, including concerns about changes in pigmented skin lesions.
There are no controlled human trials supporting tanning or libido use. The published clinical literature consists mainly of case reports and clinician warnings. Reports have described new or changing moles and darkening of pigmented lesions after use of melanocortin tanning injections (example and example), and poison-center and dermatology sources describe nausea, flushing, and other effects. These are reports and warnings, not controlled trials, and unregulated product quality adds further uncertainty.
The first human data came from a 1996 pilot study in three healthy men, which reported:
| Finding | Result |
|---|---|
| Increased pigmentation | 2 of the 3 men |
| Spontaneous erections | Lasted 1 to 5 hours |
| Mild nausea | Appeared at most dose levels |
| Grade II somnolence and fatigue | 1 of 2 men escalated to the highest dose |
It was a small drug-development study, not evidence that gray-market use is safe. The most serious skin report followed later: in one case report, a 20-year-old woman with fair skin developed melanoma after using it with a tanning bed.
Sources: case reports of pigmented-lesion changes after melanocortin tanning injections (Cardones and Grichnik, Archives of Dermatology, 2009, DOI: 10.1001/archdermatol.2008.623; Cousen et al., British Journal of Dermatology, 2009, DOI: 10.1111/j.1365-2133.2009.09362.x), indexed on PubMed; and FDA warning communications on injectable tanning products. This document is educational, is not medical advice or a health claim, and is not an offer to sell any product.
Registered human trials
2 registered human trials on ClinicalTrials.gov that we reviewed
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