Skin & aging MC1R agonist
Melanotan I
Regulatory status
Status at a glance
503A compounding status
Not nominated
We found no pending nomination for the 503A bulks list. Unless the substance has another legal pathway (for example, a USP monograph or use in an FDA-approved drug), 503A pharmacies generally may not compound with it.
- 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This is not medical or legal advice, and we do not publish dosing, sourcing or reconstitution information.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 I is a synthetic peptide that darkens skin by activating a pigment receptor, sold on the gray market as an injectable "tanning peptide." The same molecule, as the approved drug afamelanotide (Scenesse), is used for a rare light-sensitivity disorder. In two placebo-controlled trials of the approved implant in 168 adults with EPP, U.S. patients logged a median 69.4 pain-free hours in direct sunlight versus 40.8 on placebo (P = 0.04). No controlled trial supports the gray-market tanning product, which is not FDA-approved as of 2026.
At a glance
- FDA status
- As a tanning peptide, non-FDA-approved and unregulated
- What it is
- MC1R agonist that stimulates skin pigment production
- Approved form
- The identical molecule is the approved drug afamelanotide (Scenesse) for a rare disorder, which this is not
- Research
- No controlled evidence supporting unregulated self-injected tanning
- Evidence strength
- Low research
Summary
Melanotan I is a synthetic peptide that activates the MC1R pigment receptor. The gray-market tanning product is unapproved and lacks controlled evidence.
What is Melanotan I?
Melanotan I is a synthetic analog of alpha-melanocyte-stimulating hormone (alpha-MSH), a potent activator of the skin's MC1R pigment receptor. Chemically it is the same molecule as afamelanotide, the approved drug sold as Scenesse. The distinction is the product and the use: gray-market "Melanotan I" is an unregulated, self-injected tanning product, not the approved, quality-controlled implant. It is not an approved medicine in that form.
How does it work?
Melanotan I activates MC1R on pigment-producing skin cells, which raises production of the dark pigment eumelanin, darkening the skin independently of UV exposure. The receptor pharmacology is well characterized. This describes how it produces pigmentation, separate from whether unregulated self-injection for tanning is effective or safe.
In a placebo-controlled study of 65 fair-skinned volunteers, epidermal melanin density rose an average of 41% in low-MED, burn-prone skin and 12% in high-MED skin. That result shows the molecule's pigment effect, not the quality or safety of gray-market vials.
Is it FDA-approved?
Safety note
Status: As a tanning peptide, non-FDA-approved and unregulated
Category: Wellness and performance · Primary body area: Skin & aging
No, not as a tanning product. The identical molecule is FDA-approved as afamelanotide (Scenesse), a controlled-release implant for erythropoietic protoporphyria, a rare light-sensitivity disorder, given under medical supervision. Gray-market Melanotan I vials sold for cosmetic tanning are not Scenesse, carry none of its manufacturing or quality controls, and are not approved.
What does the research show?
Editor’s note
Evidence strength: Low research
The receptor pharmacology is solid, but there is no controlled human evidence supporting unregulated self-injected tanning; the only rigorous human data belong to the approved drug for a different, medical use.
The rigorous human data belong to the approved drug and a different use. Afamelanotide has clinical trial evidence for reducing phototoxicity in the rare disorder it treats, not for cosmetic tanning. There are no controlled human trials supporting unregulated self-injected Melanotan I for tanning, so its cosmetic benefit and safety as sold are unestablished.
Two placebo-controlled trials of the approved implant, reported in 2015, enrolled 168 adults with EPP, split by trial as shown below.
| Trial | Adults with EPP | Median pain-free hours in direct sunlight, afamelanotide versus placebo | P value |
|---|---|---|---|
| United States | 94 | 69.4 versus 40.8 | 0.04 |
| European Union | 74 | 6.0 versus 0.8 | 0.005 |
In the EU trial, patients also had 77 phototoxic reactions versus 146 (P = 0.04). The most common adverse events were headache, nausea, nasopharyngitis, and back pain, with mild implant-site hyperpigmentation in about one third of treated patients. These figures come from a medical implant used for EPP, so they say nothing about tanning vials.
Sources: pharmacology and bioassay work on the afamelanotide molecule (Spichty et al., Journal of Pharmaceutical and Biomedical Analysis, 2012, DOI: 10.1016/j.jpba.2012.11.040), indexed on PubMed; and FDA records for the approved product Scenesse (afamelanotide). This document is educational, is not medical advice or a health claim, and is not an offer to sell any product.
Registered human trials
0 registered human trials on ClinicalTrials.gov that we reviewed
Sources
- [1]
- [2]
- [3]
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