Viral 'Barbie drug' for tanning can cause brain swelling and even cancer, experts warn 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 Unlock Your Natural Glow with Melanotan and Say Goodbye to Hours Under the Sun Sponsored Content herald dispatch.com Melanotan II Safety: Tanning Injection LIVV Natural