Skin, hair & aesthetics
Melanotan II
A synthetic analog of alpha-MSH that darkens the skin (tanning) and increases libido. Small human trials; not approved.
How it works
It activates melanocortin receptors: MC1R darkens the skin, while MC3R and MC4R affect appetite and sexual arousal.
What it is used for
Tanning and sexual dysfunction. PT-141 (bremelanotide) was developed from it.
What the evidence says
Small trials in the 1990s showed tanning and erections. It was never approved.
Side effects and cautions
Nausea, flushing, spontaneous erections, and darker or new moles. There are reports of melanoma, and all products are unregulated.
Half-life
About 1.5 hours in animals; not established in people
Makes sense for
- Adults with fair skin who want a tan
Does not make sense for
- Many moles or a history of melanoma
- Heart disease or high blood pressure