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 Peptides are having a moment, but not all of them are harmless., One thats getting a lot of attention right now? Melanotan II., Its being used to achieve a tan from the inside, but what it Viral 'Barbie drug' for tanning can cause brain swelling and even cancer, experts warn Dangerous' tanning products promoted by influencers Melanotan What It Is and Its Relation to Skin Cancer