Melanotan 1 vs 2: Differences, Approval and Risks
Melanotan 1 vs 2 sets an approved drug against one with no US approval record. Melanotan I is afamelanotide, sold as the Scenesse implant for a rare disease that makes light painful. Melanotan II had no record in the US Drugs@FDA search we ran. Its human record is mostly hospital case reports. The US label and the EMA record approve Melanotan I for that disease only, not for tanning.
The short version
- Target: MT-1 binds mainly the skin pigment receptor. MT-2 hits several receptors, some in the brain.
- Status: MT-1 is a US and EU medicine for one disease. MT-2 has no Drugs@FDA record under the five names we searched.
- Evidence: MT-1 has label trial counts. PubMed lists 26 case reports on melanotan. 12 name MT-II, and 21 of the 26 describe a harm.
We have a full page on each molecule. This one only compares them, using the drug label on one side and the case reports on the other. See the Melanotan I profile and the Melanotan II profile for the rest.
Sources: SCENESSE (afamelanotide) implant, US prescribing information, Clinuvel, DailyMed version 11 published 13 May 2026; openFDA Drugs@FDA search for melanotan, melanotan ii, melanotan 2, melanotan-ii and mt-ii in ingredient, brand and generic names, run 23 October 2026: no matches. The same search for afamelanotide returns one record, NDA210797 (Scenesse).; PubMed search melanotan[tiab] AND case reports[pt], run 23 October 2026: 26 records on melanotan. We read every title, and the abstract where PubMed has one (14 of 26). 12 of the 26 name Melanotan II or MT-II in the title or abstract; 14 say only melanotan
Melanotan 1 and 2 side by side
We built this table from the label, the EU medicines agency, PubChem, the early studies and a live US drug database search. No other page in the top results puts the label next to the case reports, so this is our own layout. Each row names where its facts come from.
| Point | Melanotan I (afamelanotide) | Melanotan II | From |
|---|---|---|---|
| Other name | Afamelanotide. Sold as the implant Scenesse. | MT-II. No brand, and no record in the Drugs@FDA search we ran. | Label; Chawathe 2026; openFDA search |
| Shape and size | A straight chain of 13 amino acids. Weight about 1,647. | A ring of 7 amino acids. Weight about 1,024. | Label; Dorr 1996; PubChem |
| Which receptors | Binds mainly MC1-R, the pigment switch on skin cells. | Non-selective. It acts on several melanocortin receptors, including ones in the brain. | Label; Wessells 2000; Peters 2020; Molden 2015 |
| Approved use | Adults with EPP, a rare disease that makes light painful. Not approved for tanning. | None found in the US Drugs@FDA search. | Label; EMA; openFDA search |
| US approval | Yes, first approved in 2019 (NDA210797). | No Drugs@FDA record under five names we searched. | Label; openFDA search |
| EU approval | Yes, since 22 December 2014, under exceptional circumstances. | Not part of that approval. | EMA |
| Who gives it | A trained health professional places the implant. | Self-injected or sprayed when bought online, per the case reports. | Label; case reports |
| What the record shows | Trial side effect counts against a dummy implant, in the label. | Two small early studies (1996, 2000) plus case reports: 26 PubMed case records on melanotan, 12 of them naming MT-II, and 21 describing a harm. | Label; our case report count |
The receptor row explains most of the rest. A drug that sticks mainly to the skin pigment switch mostly changes skin color. A drug that also reaches brain receptors can also bring nausea, sleepiness and erections. That is what the early Melanotan II studies saw, and it is what the case reports keep describing.
One caution on the US row. A database search shows what has an approval record. It does not test what is in a bottle sold online under either name.
Sources: SCENESSE (afamelanotide) implant, US prescribing information, Clinuvel, DailyMed version 11 published 13 May 2026; European Medicines Agency, Scenesse overview page, last updated 7 October 2026; PubChem, afamelanotide, CID 16197727; PubChem, Melanotan II, CID 92432; Dorr RT and others, pilot phase I study of Melanotan II, Life Sciences, 1996. PMID 8637402; Wessells H and others, "Melanocortin receptor agonists, penile erection, and sexual motivation: human studies with Melanotan II." International Journal of Impotence Research, 2000. PMID 11035391; Molden BM and others, "Temporal cAMP Signaling Selectivity by Natural and Synthetic MC4R Agonists." Molecular Endocrinology, 2015. PMID 26418335; openFDA Drugs@FDA search for melanotan, melanotan ii, melanotan 2, melanotan-ii and mt-ii in ingredient, brand and generic names, run 23 October 2026: no matches. The same search for afamelanotide returns one record, NDA210797 (Scenesse).
What was given in the label and the first study
The two molecules come with very different records of how they were given. One is a regulated implant with a fixed schedule. The other was tested in three healthy men in the 1990s and has no Drugs@FDA record under the five names we searched.
The US Scenesse label and the EU medicines agency page set this schedule for adults with EPP:
One implant holding 16 mg of afamelanotide, placed under the skin
One implant every 2 months
EU page: three implants a year recommended, four at most
Disclaimer: this is the approved schedule for a prescription implant in one rare light disease, placed by a trained professional. It is shown to report the label. It is not a tanning dose or a dose for anyone, and powder sold online as Melanotan I is not Scenesse.
The 1996 pilot study by Dorr and colleagues in Life Sciences gave Melanotan II by shot to three healthy men, at these amounts:
Starting amount: 0.01 mg per kg of body weight
Highest amounts reached: 0.025 to 0.03 mg per kg
Disclaimer: these figures come from a three-person safety study, shown only to report what it tested. They are not a dose. No US label sets a Melanotan II dose, since the Drugs@FDA search found no record for it. At the highest amount, one of two men had marked sleepiness and tiredness.
In that study, mild nausea showed up at most amounts tested. The men also had yawning and stretching, then erections lasting one to five hours. Two of the three got darker skin. A later study in 20 men with erection problems found erections in 17 of them, with nausea and yawning as common side effects.
Sources: SCENESSE (afamelanotide) implant, US prescribing information, Clinuvel, DailyMed version 11 published 13 May 2026; European Medicines Agency, Scenesse overview page, last updated 7 October 2026; Dorr RT and others, pilot phase I study of Melanotan II, Life Sciences, 1996. PMID 8637402; Wessells H and others, "Melanocortin receptor agonists, penile erection, and sexual motivation: human studies with Melanotan II." International Journal of Impotence Research, 2000. PMID 11035391
What the Melanotan I label reports
The Scenesse label pools three trials of 244 adults with EPP. In them, 125 people got the real implant and 119 got a dummy implant. Here are the side effects it lists, with the counts as printed.
| Side effect | Real implant | Dummy implant |
|---|---|---|
| Implant site reaction | 26 of 125 (21%) | 12 of 119 (10%) |
| Nausea | 24 of 125 (19%) | 17 of 119 (14%) |
| Fatigue | 7 of 125 (6%) | 3 of 119 (3%) |
| Melanocytic nevus (mole) | 5 of 125 (4%) | 2 of 119 (2%) |
| Skin hyperpigmentation | 5 of 125 (4%) | 0 of 119 (0%) |
| Dizziness | 5 of 125 (4%) | 4 of 119 (3%) |
The label also warns that the drug can darken the whole skin and make existing moles and freckles darker. It advises a full body skin check twice a year. Serious allergic reactions, including anaphylaxis, have been reported since it went on sale. The EU page names nausea, headache and implant site reactions as the most common effects.
Sources: SCENESSE (afamelanotide) implant, US prescribing information, Clinuvel, DailyMed version 11 published 13 May 2026; European Medicines Agency, Scenesse overview page, last updated 7 October 2026
What the melanotan case reports show
There is no label for Melanotan II, so its safety record is mostly doctors writing up single patients. On 23 October 2026 we pulled every PubMed record tagged as a case report that mentions melanotan. There were 26. We read each title, and each abstract where one exists, and sorted them by the main problem described. Only 12 of the 26 name Melanotan II or MT-II in the title or abstract. The other 14 say only melanotan.
| Main problem in the report | Records of 26 |
|---|---|
| New or changing moles | 9 |
| Melanoma | 3 |
| Other dark patches (gums, nails) | 2 |
| Painful long erection (priapism) | 2 |
| Kidney or muscle damage | 2 |
| Brain swelling syndrome | 1 |
| Whole-body stimulant symptoms | 1 |
| Skin ulcers at the shot site | 1 |
| No patient harm described, or no abstract | 5 |
Of the 26, 21 describe a patient harm, and 15 of those are about the skin, moles or pigment. That matches a 2017 review in the International Journal of Dermatology, which counted four reports of melanoma rising from existing moles during or soon after melanotan use. The review also says firm proof of cause is lacking.
The other reports reach past the skin. A Swedish team linked Melanotan II to loss of blood flow in part of a kidney. A US poison center described muscle breakdown and kidney strain after one large shot. Two urology teams treated painful erections that would not go down.
Read this table with care. Case reports show that something happened after use. They cannot show how often it happens or prove the drug caused it. Some patients also used sunbeds or other drugs. Twelve of the 26 records have no abstract on PubMed, so for many of them the product is named only as melanotan.
Sources: PubMed search melanotan[tiab] AND case reports[pt], run 23 October 2026: 26 records on melanotan. We read every title, and the abstract where PubMed has one (14 of 26). 12 of the 26 name Melanotan II or MT-II in the title or abstract; 14 say only melanotan; Habbema L and others, "Risks of unregulated use of alpha-melanocyte-stimulating hormone analogues: a review." International Journal of Dermatology, 2017. PMID 28266027; Peters B and others, "Melanotan II: a possible cause of renal infarction: review of the literature and case report." CEN Case Reports, 2020. PMID 31953620; Nelson ME and others, "Melanotan II injection resulting in systemic toxicity and rhabdomyolysis." Clinical Toxicology, 2012. PMID 23121206
What the top pages for this search cite
On 23 October 2026 we read the pages that rank for this search in the US. Six of nine could be read as text. Here is what we counted, using a script over our saved copies:
- 5 of 6 named Scenesse or afamelanotide.
- 0 of 6 linked the drug label or the EU product page.
- 1 of 6 named a specific published case report.
- 3 of 6 printed amounts in mg or mcg.
So the approved drug gets named, but its own record rarely gets shown. This is our snapshot of one search on one day, not a survey. It is why this page leans on the label and the case reports instead of claims.
Sources: Our own read of the top US results for "melanotan 1 vs 2", 23 October 2026
Where PT-141 fits
PT-141, or bremelanotide, is the third member of this family. A 2012 report calls it a variation of Melanotan II, built for sexual effects. It reached US approval in 2019 as Vyleesi, for low sexual desire in some women before menopause.
Its label says it acts on several receptors, strongest at MC1R and then MC4R. It also warns about dark patches of skin, including on the face and gums. Our PT-141 calculator covers its vial math.
Sources: Nelson ME and others, "Melanotan II injection resulting in systemic toxicity and rhabdomyolysis." Clinical Toxicology, 2012. PMID 23121206; VYLEESI (bremelanotide) injection, US prescribing information, DailyMed
Common questions
Should I take Melanotan-1 or 2?+
This page cannot answer that for anyone. The facts are these. In the US label and the EMA record we read, Melanotan I is approved only as the Scenesse implant, for adults with a rare light disease, and a trained professional places it. Neither record covers tanning. Melanotan II had no Drugs@FDA record under the five names we searched. Its human record is mostly case reports of harm.
What is the difference between Melanotan-1 and Melanotan 2?+
Melanotan I, also called afamelanotide, is a longer peptide that binds mainly the skin pigment receptor. Melanotan II is a smaller ring-shaped peptide that acts on several receptors, including some in the brain. That wider reach is why it is tied to erections, nausea and yawning in studies. Melanotan I is an approved medicine for one disease in the US and EU records we read. The Drugs@FDA search we ran found no record for Melanotan II.
Do you need to tan with Melanotan-1?+
The Scenesse label says afamelanotide raises eumelanin, the dark skin pigment, without sun or UV light. The same label tells patients to keep up sun and light protection. The label describes a medicine for a light disease, not a tanning product.
Can melanotan 2 affect the brain?+
Melanotan II reaches receptors in the brain, which is one way it differs from Melanotan I. A 2013 report in the Annals of Internal Medicine linked melanotan to posterior reversible encephalopathy syndrome, a type of brain swelling. That is one case report, not a trial, so it shows a reported event, not a measured risk.
Does melanotan cause fat loss?+
The two human Melanotan II studies on this page do not report it. The abstracts of the 1996 Dorr pilot study in Life Sciences and the 2000 Wessells review of erection studies cover tanning, erections, nausea and sleepiness, not fat or body weight. Melanotan II acts on MC4R, a brain receptor that helps control energy balance in lab research. A lab signal like that is not proof of fat loss in people.
Is Melanotan II related to PT-141?+
Yes. A 2012 toxicology report describes bremelanotide, also called PT-141, as a variation of Melanotan II designed for sexual effects. Bremelanotide is approved in the US as Vyleesi for low sexual desire in some women before menopause. Its label lists dark patches of skin as a reported side effect.
Sources: SCENESSE (afamelanotide) implant, US prescribing information, Clinuvel, DailyMed version 11 published 13 May 2026; Kaski D and others, "Melanotan and the posterior reversible encephalopathy syndrome." Annals of Internal Medicine, 2013. PMID 23648958; Molden BM and others, "Temporal cAMP Signaling Selectivity by Natural and Synthetic MC4R Agonists." Molecular Endocrinology, 2015. PMID 26418335; Nelson ME and others, "Melanotan II injection resulting in systemic toxicity and rhabdomyolysis." Clinical Toxicology, 2012. PMID 23121206; VYLEESI (bremelanotide) injection, US prescribing information, DailyMed
Related pages
This page compares two melanocortin peptides using a drug label, regulator pages and published reports. It is background reading, not medical advice. It is not a guide to using either one, and it picks no amount for any reader.