A non-selective α-MSH analogue that increases melanin, reduces appetite, and enhances libido.
A cyclic lactam analogue of α-MSH with higher potency and protease resistance. Activates MC1R (melanin), MC3R (appetite suppression, energy balance), MC4R (libido, sexual arousal, appetite), and MC5R (exocrine glands). The broad melanocortin receptor activation produces multiple simultaneous effects.
Melanotan II was originally synthesised at the University of Arizona as a potential photoprotective agent. Its potent melanocortin receptor activity produces tanning without UV — but also erections, appetite suppression, and nausea at higher doses.
PT-141 (Bremelanotide) was derived from Melanotan II after researchers observed its sexual arousal effects. PT-141 is now FDA-approved for hypoactive sexual desire disorder in women.