Here's the part nobody explains when they're selling you the "Barbie drug.", , Melanotan 2 is a synthetic peptide that mimics alpha MSH a hormone your body already makes to tell your skin cells to How Long Does It Take For Melanotan 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 Emerging Threat: Melanotan, Repackaging, and Online Sales What is Melanotan II the drug that the TGA urges consumers to avoid?