The "Barbie Drug" Has a Dark Side Nitisinone increases melanin in people with albinism National Institutes of Health (NIH) How Melanotan 2 Affects Hair Colour Especially in Red or Ginger Hair Pure MT2 Melanotan What It Is and Its Relation to Skin Cancer 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