How Melanotan Peptides Work to Enhance Skin Tone and Promote Tanning Age Well ATL How Long Does Melatonin Take to Work? Melanotan II Safety: Tanning Injection LIVV Natural 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 I accidentally undid years of skin work and didnt realize it until it was too late., At the beginning of November, I started taking melanotan 2 and honestly?, I loved it., My tan deepened