Melanotan II Wikipedia Your body already makes a hormone that tells your skin to tan. Melanotan 2 is a synthetic peptide engineered to mimic that hormone but in a version that's more potent and longer lasting than Melanotan What It Is and Its Relation to Skin Cancer Viral 'Barbie drug' for tanning can cause brain swelling and even cancer, experts warn Melanotan 2 doesn't just stimulate melanin in your skin, but your hair follicles aswell .. my beard is about 80% darker today, than a month before I started taking melanotan. Guys with