What is Melanotan I (Afamelanotide)? What it does, benefits and what the evidence shows

Melanotan I (MT-I) is the research name for afamelanotide, a synthetic copy of alpha-melanocyte-stimulating hormone (alpha-MSH), the signal that makes skin produce dark pigment. It is one of the few compounds in this series with an FDA approval: since 2019 it has been sold as Scenesse, a small implant placed under the skin by a trained clinician, indicated to increase pain-free light exposure in adults with a history of phototoxic reactions from a rare inherited disorder called erythropoietic protoporphyria (EPP). The approval is not for tanning, and the vials sold online as Melanotan I are a different product with no label, no clinical oversight and no matching safety monitoring.

What Melanotan I is and how it works

Afamelanotide is a 13-amino-acid straight-chain peptide. The FDA label describes it as a synthetic analogue of alpha-MSH that acts as a melanocortin receptor agonist, binding predominantly to the skin pigment receptor MC1-R, and says it increases production of eumelanin (the dark pigment) in skin independently of exposure to sunlight or artificial UV (Scenesse prescribing information, DailyMed). Early human tanning studies used the same molecule under its research name, [Nle4-D-Phe7]-alpha-MSH (Dorr et al., Photochemistry and Photobiology, 2000).

Two things make it a different animal from its sibling Melanotan II. It acts mainly on the skin receptor rather than across several melanocortin receptors, and it is the version that went through full drug development. Our Melanotan II guide covers the ring-shaped peptide with the sexual effects and the safety reports; the approved bremelanotide relative is in the PT-141 guide. One curiosity from the label: the chain ends in the sequence Lys-Pro-Val, the same three amino acids that make up the small fragment covered in our KPV guide.

What is actually approved

The DailyMed record for Scenesse (label version dated May 2026, Clinuvel Inc.) lists one indication: to increase pain-free light exposure in adult patients with a history of phototoxic reactions from EPP, with initial US approval in 2019. The product is a controlled-release implant, a small rod of the peptide mixed with a biodegradable polymer, and the label says it must be administered by a health care professional who is proficient in the implantation procedure and has completed the manufacturer's training program. Safety and effectiveness in children have not been established (Scenesse prescribing information, DailyMed).

The European Union also authorized afamelanotide for EPP, as a condition of which regulators required a post-authorization safety study and a disease registry (Homey et al., Photodermatology, Photoimmunology & Photomedicine, 2025).

Approved implant versus grey-market vials

The gap is not just paperwork. The implant is a licensed, sterile product, its safety was studied in trials with defined monitoring, and the label tells prescribers to watch skin lesions. A vial sold online may contain what it says or something else, and no clinician is looking at your moles. We cannot say what any particular vial contains; that is what lab reports are for.

What people use it for

What the research actually shows

EPP: the approved use

EPP makes light cause severe burning pain. In two multicenter, randomized, double-blind, placebo-controlled trials (74 patients in the European Union and 94 in the United States), pain-free time in direct sunlight was longer with afamelanotide: a median of 69.4 hours versus 40.8 in the US trial and 6.0 versus 0.8 in the EU trial, with fewer phototoxic reactions in the EU trial and better quality of life in both; adverse events were mostly mild (Langendonk et al., New England Journal of Medicine, 2015). The FDA label reports the same two studies with slightly different medians for the US trial, 64.1 hours versus 40.5 (Scenesse label).

Those are meaningful gains for a small population with an inherited disease and a markedly reduced quality of life. They are not results in healthy people. In a German observational safety study of 200 patients treated under the European label, quality of life rose significantly from baseline and 91.0% of patients who started treatment were still on it, with a safety profile in line with the trials (Homey et al., 2025).

Tanning in healthy volunteers

In seven healthy volunteers with tanning-capable skin types, a short course of MT-I under the skin darkened the face, neck and forearm, and skin biopsies showed a large rise in eumelanin with no significant change in pheomelanin (Dorr et al., 2000). This is where the "sunless tan" claim comes from. It is a real effect, from a seven-person study, in a controlled research setting.

Vitiligo

In a randomized multicenter trial of 55 people with nonsegmental vitiligo, afamelanotide implants plus narrowband UVB light produced faster and greater repigmentation than light alone (48.64% versus 33.26% repigmentation at day 168), with the effect more noticeable in darker skin types; nausea and minor infections were among adverse events noted in the combination group (Lim et al., JAMA Dermatology, 2015). A larger Phase 3 comparison from the same sponsor is registered on ClinicalTrials.gov as active but no longer recruiting, with an estimated completion of June 2026 (NCT06109649). In a July 2026 announcement to the Australian stock exchange, the sponsor said the study has enrolled 210 patients and that topline results are expected in December 2026 (Clinuvel ASX announcement, July 2026). No results are published yet, so vitiligo remains an unapproved use.

UV redness and "protection"

A small exploratory study in nine healthy adults found that after an afamelanotide implant, UV-induced skin redness was lower (Griffin et al., 2026). Nine people over a short window is a hypothesis-generator. We found no study showing that an MT-I tan protects against skin cancer, and a tan is not a substitute for that evidence.

Side effects and risks

Label safety data. In three vehicle-controlled trials of 244 adults with EPP, the most common reactions were implant-site reactions (21% on Scenesse versus 10% on placebo), nausea (19% versus 14%), oropharyngeal pain, cough, fatigue, dizziness, skin hyperpigmentation (4% versus 0%), sleepiness and melanocytic nevus (4% versus 2%). Serious hypersensitivity reactions, including anaphylaxis, have been reported after approval (Scenesse label).

Moles. The label warns that afamelanotide may darken existing nevi and freckles because of its pharmacologic effect, and recommends regular full-body skin examinations to monitor pigmented lesions (Scenesse label). In a study of 15 EPP patients whose 103 moles were examined under dermoscopy, changes were reversible and none suggested malignancy, and no new moles appeared (Arisi et al., 2021). That is reassuring for supervised use with lesion checks; it is not a study of unsupervised use.

Unregulated use. A 2017 dermatology review said that afamelanotide has been thoroughly tested and deemed safe for its approved indication, but that illegal melanotans are likely risky for several reasons: uncertain preparation, administration and dosage, and case reports linking unregulated use of both melanotan I and II to changes in existing moles and new atypical nevi. It counted four case reports of melanomas emerging from existing moles during or shortly after melanotan use, with conclusive evidence of a link lacking (Habbema et al., International Journal of Dermatology, 2017). Many of those reports do not specify which melanotan was used, and the more severe reports we found (priapism, muscle and kidney injury) concern Melanotan II, not MT-I; see the MT-II guide.

Pregnancy and children. The label says there are no data in pregnant women and that pediatric safety and effectiveness have not been established.

What the lab tests show

As of September 29, 2026, VendorVerify's database has three Melanotan I vials from two vendors, with reports dated March 2025, April 2025 and August 2026. Purity ranged from 99.72% to 99.85%, and all three measured about 5% to 8% over their labelled amount. One vial has an endotoxin result, a pass. None of the three met our failure definition (empty, under 95% pure, more than 20% under label or more than 50% over). Three vials say nothing about the market or about any vendor, and purity and amount do not tell you about sterility, or about how the product would behave in your body. Compound-level results are on the Melanotan I results page, and you can add to them by submitting a report.

Because we don't have enough lab data on this compound to rank vendors for it, here are the highest-ranked vendors across all compounds right now. A vendor's overall record is a signal, not a guarantee for a compound they have never had tested.

Buying smarter

With only three vials on file, lean on the general checks. Look at each vendor's full record and how many reports sit behind the score. Treat a vendor-posted COA as a starting point (how to read a peptide COA, fake peptide COAs). Paying for identity, purity and quantity testing on your own vial is worth considering, and endotoxin testing matters for anything injected; how to get a peptide tested walks through it. Underdosed peptides explains why measured amounts and labels often differ.

If a report comes back with a fail, stop using that batch, tell anyone who bought from the same run, bring the report to the vendor, and submit it to VendorVerify. If you have EPP or another photosensitivity disorder, the approved product is prescribed through specialist clinics, which is a different route from anything discussed above. More reading: Melanotan II, PT-141, and the peptide hub.

Database figures are from VendorVerify as of September 29, 2026. This isn't medical advice; afamelanotide is approved only as the Scenesse implant for one condition, and vials sold as Melanotan I are unregulated research chemicals.