Melanotan II
Small early human studies showed tanning. Never approved, with documented safety concerns.
At a glance. A synthetic tanning peptide that acts on several receptors at once, which is where most of its side effects come from.
We do not sell Melanotan to anyone who has a large number of moles, or any personal history of melanoma or skin cancer. Melanotan darkens existing moles, which makes changes in them harder to spot, and spotting those changes early is how skin cancer is caught.
Written and maintained by the AVERON Research Desk · Last reviewed September 2026
What it is
Melanotan II is a synthetic cyclic peptide that mimics alpha-melanocyte-stimulating hormone, the natural hormone that tells skin cells to produce the pigment melanin. It was developed at the University of Arizona in the 1980s and 1990s, originally with the idea of producing a protective tan with less sun exposure.
Unlike Melanotan I, it is non-selective: it activates several melanocortin receptors, not only the one responsible for pigment. Its action on the other receptors explains its well-known effects on sexual arousal and appetite.
What researchers study it for
Skin pigmentation, and, through its action on other receptors, sexual function. Research into its sexual effects contributed to the development of bremelanotide, now approved as PT-141.
What the research shows
Small early human studies in the 1990s found that Melanotan II increased skin pigmentation, and separately that it could induce erections in men. These studies were short and involved small numbers of participants.
Melanotan II was never taken forward to approval. Since then, the published literature on it consists largely of case reports of problems in people using unregulated products.
What it does not do, and what is not known
- It does not tan skin on its own. It amplifies the skin's response to ultraviolet light.
- It does not protect against sun damage or skin cancer.
- It is not selective: the effects on libido, appetite and nausea come with the tan.
- Its long-term safety has never been studied.
- It has never been approved by any regulator.
Adverse effects reported in research
Nausea and facial flushing are very common, particularly on first exposure. Spontaneous erections are commonly reported in men. Darkening of existing moles and freckles, and the appearance of new moles, are well documented.
Case reports have described melanoma, including a report by Hjuler and Lorentzen in Dermatology in 2014, along with rapidly changing moles, prolonged painful erections, muscle breakdown and kidney problems.
Regulatory and anti-doping status
Regulatory: Not approved as a medicine anywhere. Regulators including the UK's Medicines and Healthcare products Regulatory Agency and Australia's Therapeutic Goods Administration have warned the public against using it.
Anti-doping: With no approval for human therapeutic use, it falls under WADA's category S0 (non-approved substances). Prohibited at all times in tested sport.
At AVERON
Supplied as research-grade material, Melanotan II 10 mg, subject to the restriction at the top of this page.
Independent lab report: 112973_CQGH6QRK44VN
Frequently asked questions
Doses mentioned on this page are the arms of published studies or the terms of an approved product, given to describe the evidence. They are not guidance.