Melanotan 1 vs Melanotan 2: one became a medicine, one never did

The names Melanotan 1 and Melanotan 2 sound like two versions of the same product. They are not. Melanotan 1 and Melanotan 2 came out of the same research group and both copy the hormone that tells skin to make pigment, but their stories split hard. The molecule first called Melanotan 1 went through full clinical trials and became a prescription implant for a rare light-sensitivity disorder. Melanotan 2 never made that trip and is not approved for anything. This page lays the two side by side: what each one is, what the research shows, how their side effects differ, and why dermatologists keep warning about both. It is educational only, with a primary source for every claim, and nothing here is medical advice. For the single-substance overview, see our Melanotan II page.

What is the difference between Melanotan 1 and Melanotan 2?

The short version: Melanotan 1 is a tested drug with one narrow approval, and Melanotan 2 is an untested research chemical with a wider set of effects. Melanotan 1 is the research name for afamelanotide (Mun et al., International Journal of Molecular Sciences, 2023), a synthetic 13-amino-acid copy of alpha-melanocyte-stimulating hormone (α-MSH) (Scenesse label). Melanotan 2 is a shorter, ring-shaped (cyclic) peptide built from a seven-amino-acid stretch of the same hormone (Dorr et al., Life Sciences, 1996). The two also act differently: the 2023 review notes that Melanotan II is weaker than Melanotan I at activating pigment cells but has a stronger sexual effect, which is why Melanotan 2 is known for effects well beyond the skin.

Sources for the table are cited in the sections below.

What is Melanotan 1?

Melanotan 1 is a synthetic version of α-MSH with two amino-acid swaps that make it more stable and more potent than the natural hormone. Researchers named it [Nle4, D-Phe7]-α-MSH, also written NDP-MSH, and its official drug name is afamelanotide (Mun et al., 2023). The FDA label for its approved form describes afamelanotide as a synthetic 13-amino-acid peptide that binds predominantly to the melanocortin 1 receptor (MC1R) and increases eumelanin in the skin independently of sun or UV exposure.

Its tanning effect was shown early. In a 1991 randomized, double-blind, placebo-controlled trial in 28 healthy white men, injections of the peptide darkened skin in both poor-tanning and good-tanning skin types, while no darkening occurred on placebo. The authors concluded that tanning “appears possible” without UV exposure. That line launched decades of interest, but the molecule’s eventual approval was for a medical condition, not cosmetic tanning.

What is MT2?

MT2 is short for Melanotan II, a cyclic, lactam-bridged peptide built on a short piece of α-MSH that the researchers who first tested it in people called “superpotent” in lab assays (Dorr et al., 1996). In that three-man pilot study, two men showed increased pigmentation of the face, upper body and buttocks, and the peptide also produced nausea, a stretching-and-yawning response, and spontaneous erections lasting hours (Dorr et al., 1996).

The erection effect is the key difference from Melanotan 1. The 2023 review credits Melanotan II with a stronger sexual effect, and a small 1998 placebo-controlled crossover study found it initiated erections in 8 of 10 men with psychogenic erectile dysfunction. A 2012 case report in Clinical Toxicology describes bremelanotide as a variation of Melanotan II designed for sexual stimulation, and bremelanotide, sold as Vyleesi, is FDA-approved for one narrow use, low sexual desire in premenopausal women. MT2 itself never went through that approval process.

Is Melanotan 1 FDA approved?

Afamelanotide, the molecule first called Melanotan 1, has a U.S. approval, but only in one form for one use. Scenesse, an afamelanotide implant, carries an initial U.S. approval of 2019 and is indicated to increase pain-free light exposure in adults with a history of phototoxic reactions from erythropoietic protoporphyria (EPP), a rare disorder that makes light exposure painful. The European Commission authorised Scenesse on 22 December 2014, under “exceptional circumstances”. It is not approved for cosmetic tanning anywhere, and powders sold online as “Melanotan 1” are not the approved implant.

How and why do people use Melanotan 1 and 2?

Almost all non-medical use is about tanning. A 2017 review in the International Journal of Dermatology says unregulated users take melanotan I and II primarily for their tan-stimulating effects, and a 2015 review of the clinical literature traces the black market to a socio-cultural emphasis on having a tan. Melanotan 2 has a second draw: the 2012 Clinical Toxicology case report notes that melanotan products bought online are used for sunless tanning and also as sexual stimulants.

A 2021 study in the journal Dermatology read 623 forum posts from 205 people discussing Melanotan II on UK and Irish forums. It found people used it mainly for a tanned look, often ahead of sun holidays and fitness or bodybuilding competitions. The same study found misinformation, product preparation, dosing regimens, and sunbed use alongside it were common themes (Gilhooley et al., 2021).

What does the research show for each?

The evidence gap between the two is the whole story. For Melanotan 1, the evidence level is “approved drug, labeled use.” Two randomized, double-blind, placebo-controlled trials in people with EPP, 74 patients in Europe and 94 in the United States, found the implant increased hours of direct sunlight without pain and improved quality of life, with mostly mild adverse events. That is a real result, but it was measured in a rare disease, with a slow-release implant given by clinicians, not in healthy people injecting powder for a tan.

For Melanotan 2, the evidence level is “very small early human studies.” The early human data include a three-person pilot study and a small crossover study of ten men. A 2015 review of all clinical trials and case reports on both melanotans found eighteen clinical trials and twenty-one case presentations, and noted that long-term health outcomes are undocumented. The 2017 dermatology review sums up the split: afamelanotide has been thoroughly tested and is the only α-MSH analogue approved for a limited number of medical uses, while the unregulated melanotans are untested.

How do the side effects compare?

Both darken moles and both cause nausea, but Melanotan 2 reaches further into the body. In the Scenesse trials, the most common adverse reactions were implant-site reactions (21% versus 10% on placebo), nausea (19% versus 14%), and smaller rates of cough, fatigue, dizziness, skin darkening and moles. Even this tested product carries a skin warning: the label says it may darken existing moles and freckles and recommends a full-body skin examination twice a year.

Melanotan 2 adds effects beyond the skin. Early studies recorded nausea, yawning and stretching, and spontaneous erections, plus decreased appetite. Case reports go further: one documents priapism after a Melanotan II overdose, and another describes a man who developed a racing heart, muscle breakdown (rhabdomyolysis) and kidney injury after injecting a large amount.

The mole question applies to both unregulated melanotans. The 2017 review links unregulated use of both melanotan I and II to changes in existing moles and new, sometimes dysplastic, moles, and counts four case reports of melanoma arising during or shortly after use. The authors note conclusive proof of cause is lacking, but a drug that darkens and multiplies moles also makes the ones worth watching harder to read.

Is MT2 safe?

There is no evidence that it is, and the documented risks are serious. Melanotan II has never completed the large trials that would establish its safety, and its case reports include priapism, systemic toxicity and mole changes. The Skin Cancer Foundation’s July 2026 warning says it is not approved by the FDA for any use and its safety has not been established, and points people to sunless self-tanners instead. Product quality is a separate risk: the 2017 review flags questions about the preparation, administration and dosage of unregulated vials, and the forum study raised contaminated products and infection transmission.

Can you compare Melanotan 1 and 2 on cost or access?

Not on equal terms, because they reach people through completely different routes. Afamelanotide is a specialist prescription for EPP, and the label says the implant should be administered by a healthcare professional trained in the implantation procedure. Melanotan 2 is sold online as a “research use only” product with no approved label, and the 2017 dermatology review raises questions about the preparation, administration and dosage of unregulated melanotans. Comparing the two on price misses the point; what you are paying for is entirely different. PeptideAgent’s Melanotan I vs Melanotan II comparison lands in the same place on access: neither is approved for cosmetic tanning, and injectable vials of either sold online are unapproved drugs.

What is the community saying?

The best look at the conversation comes from the 2021 forum study of Melanotan II users, which found the talk centered on getting a tan before holidays and competitions, dosing regimens, preparing the product, and using sunbeds alongside it. It also found misinformation was a recurring theme. The fact-check worth repeating from all of this: when someone says Melanotan 1 is an approved drug, what is approved is the Scenesse implant for one rare disease, not a vial of “MT1” or any tanning use.

How to think about Melanotan 1 vs 2

The useful frame is the one the evidence draws. Melanotan 1 shows what this chemistry looks like after real trials: a narrow medical use, a known side-effect list, and a label that still asks for twice-yearly skin checks. Melanotan 2 shows the same chemistry without that work: broader effects, case reports of emergencies, and no product standard. If the goal is a tan, the Skin Cancer Foundation points to sunless self-tanners. If what you actually want is a skin routine built around topical peptides and daily sunscreen, our sister site walks through building a peptide skin routine safely. Anyone who has used either melanotan has good reason to get their moles checked by a dermatologist.

Status (Melanotan II): Not FDA-approved for any use. What this status means.

Educational information only, not medical advice. Every scientific statement on this page is sourced to the primary references linked above. Updated October 12, 2026.