Synthetic analog of melanocyte-stimulating hormone. Studied in the 1990s for erectile dysfunction and today circulates without oversight as an "injectable tanner," not approved in any country.
Regulatory status
Not approved
Family
Melanocortin receptor agonist (α-MSH analog)
Scientific evidence
Low
Number of findings
3
Where it acts
Sexual and reproductive · Skin and aging
Also known as
Melanotan II, MT-II, MT-2, melanotan-2
Regulatory status
FDA (US): Not approved. The FDA lists it among substances with safety risks for compounding (melanoma, encephalopathy, and priapism described in case reports).
EMA (EU): Not approved. Not to be confused with afamelanotide (Scenesse), a different analog that is authorized by the EMA for erythropoietic protoporphyria.
Dose
In two small trials, a single dose of 0.025 mg/kg subcutaneously was used (Wessells 1998 and 2000). There is no approved regimen.
Safety
In trials: nausea (sometimes severe), yawning, stretching, and loss of appetite. Outside trials, darkening and appearance of atypical moles, cases of melanoma, priapism, and other serious conditions have been described. Black-market products have no quality control. Its use only makes sense in research or under medical supervision; buying it is not recommended.
Differences between women and men
Clinical trials were conducted only in men (erectile dysfunction). Its derivative bremelanotide is approved in the US for premenopausal women with hypoactive sexual desire.
Effect by goal · level of evidence
Erections in psychogenic erectile dysfunction
improvesLowRCT (AA)in people
38 vs 3 min
Double-blind crossover trial with 10 men: 8 of 10 had visible erections. Useful rigidity lasted an average of 38 minutes vs 3 with placebo.
Erections and desire in organic erectile dysfunction
improvesLowRCT (AA)in people
12/19 vs 1/21
Crossover trial with 10 men with organic risk factors: an erection occurred after 12 of 19 injections vs 1 of 21 with placebo, along with more sexual desire. 4 of 19 injections caused severe nausea.
Review of clinical cases: unregulated use is associated with changes in existing moles and new dysplastic nevi; four melanomas are described. A causal relationship has not been shown.
Activates several melanocortin receptors at once. In the skin (MC1R) it stimulates melanin production and darkens skin tone. In the brain (MC3R/MC4R) it promotes erection and reduces appetite. This lack of selectivity explains both its effects and many of its adverse effects.
What the evidence says
In people
Erections in psychogenic erectile dysfunction. Double-blind crossover trial with 10 men: 8 of 10 had visible erections. Useful rigidity lasted a mean of 38 minutes vs 3 with placebo. PubMed 9679884
Erections and desire in organic erectile dysfunction. Crossover trial with 10 men with organic risk factors: there was an erection after 12 of 19 injections vs 1 of 21 with placebo, and more sexual desire. 4 of 19 injections caused severe nausea. PubMed 11018622
Mole changes and melanoma cases. Review of case reports: unregulated use is associated with changes in existing moles and new dysplastic nevi; four melanomas are described. A causal relationship has not been demonstrated. PubMed 28266027