Melanotan I
A synthetic analogue of α-MSH that stimulates skin pigmentation. Unlike Melanotan II, one formulation (afamelanotide / Scenesse) is FDA-approved as an implant for a rare light-sensitivity disorder.
Quick take
- What it is: a lab-made version of α-melanocyte-stimulating hormone (α-MSH) that drives melanin production in the skin.
- What people use it for: medically, to reduce phototoxic pain in erythropoietic protoporphyria; informally, to darken skin (tanning).
- What we actually know: as the approved implant afamelanotide, it has solid trial data for EPP; cosmetic injectable use is far less studied.
- Status: the afamelanotide implant (Scenesse) is FDA-approved for a rare disease; general cosmetic / tanning use is not approved.
What it is
Melanotan I is a synthetic analogue of α-melanocyte-stimulating hormone (α-MSH), the natural hormone that signals skin cells to produce the pigment melanin. As a pharmaceutical it is known as afamelanotide and is sold under the brand name Scenesse as a slow-release subcutaneous implant.1
It is important to keep Melanotan I distinct from Melanotan II: they are different molecules with very different regulatory standing. Melanotan I has an approved medical formulation, whereas Melanotan II does not.
How it works
Melanotan I activates the melanocortin-1 receptor (MC1R) on pigment-producing skin cells (melanocytes), increasing the synthesis of eumelanin. More melanin provides some natural protection against ultraviolet and visible light, which is the basis for its approved use in a light-sensitivity disorder.1,2
Because it acts on the melanocortin system, it can also produce darkening of existing moles and freckles, which is relevant to monitoring during use.
What the evidence shows
Animal studies
Preclinical work established that α-MSH analogues reliably stimulate melanogenesis through MC1R, providing the mechanistic rationale that was later tested in people.2
Human studies
Afamelanotide has been evaluated in randomised controlled trials in patients with erythropoietic protoporphyria (EPP), a rare inherited disorder in which sunlight causes severe pain. In these trials it increased the time patients could spend in light without pain, which supported its regulatory approval.3 Evidence for purely cosmetic tanning use is limited and was not the basis for approval.
Dosages reported in the literature
Informational only. The figures below describe how the approved product and reported protocols have been used in studies. They are not a recommendation or a prescription. Appropriate use, if any, should be determined by a qualified healthcare professional.
| Setting | Route | Reported range |
|---|---|---|
| EPP (approved product) | Subcutaneous implant | One 16 mg implant every ~2 months, as labelled |
| Research / cosmetic (unregulated) | Subcutaneous injection | Variable microgram-range protocols; not standardised |
Only the implant dosing reflects an approved, studied regimen. Injectable protocols sold for tanning are not standardised and should not be read as established as safe or effective.
Safety & side effects
In clinical trials of the approved implant, commonly reported effects included nausea, headache, fatigue and skin reactions at the implant site, along with darkening of skin and moles.3 Because the peptide darkens pigmented lesions, periodic skin monitoring is sensible during use.
A major separate concern is that unregulated Melanotan products bought online are not the approved drug. Their purity, dose and sterility are uncertain, and they have been linked to adverse reports in regulatory safety communications.4
Legal & regulatory status
The afamelanotide implant (Scenesse) is FDA-approved for increasing pain-free light exposure in adults with a history of phototoxic reactions from EPP.1 That approval is narrow. General cosmetic, tanning or injectable use of Melanotan I is not approved, and several regulators have warned against unlicensed injectable tanning products.4 Rules differ by country and change over time.
References
- U.S. Food and Drug Administration. FDA approves first treatment to increase pain-free light exposure in patients with a rare disorder (Scenesse / afamelanotide implant, NDA 210797). FDA News Release, October 8, 2019. (See also: SCENESSE [afamelanotide] implant Prescribing Information / Highlights of Prescribing Information, FDA, 2019/2023.) [fda.gov]
- Böhm M, et al. An overview of benefits and risks of chronic melanocortin-1 receptor activation. J Eur Acad Dermatol Venereol (JEADV). 2025;39(1):39-51. doi:10.1111/jdv.20269. [PMID 39082868, doi:10.1111/jdv.20269]
- Langendonk JG, Balwani M, Anderson KE, Bonkovsky HL, Anstey AV, Bissell DM, et al. Afamelanotide for Erythropoietic Protoporphyria. N Engl J Med. 2015;373(1):48-59. doi:10.1056/NEJMoa1411481. [PMID 26132941, doi:10.1056/NEJMoa1411481]
- Medicines and Healthcare products Regulatory Agency (MHRA). Warning against use of unlicensed Melanotan I and II tanning injections and nasal sprays (consumer/Drug Safety warning), gov.uk. (See also: U.S. FDA warning that injectable melanotan tanning products are mislabeled, marketed and sold illegally.) [gov.uk]