95% (HPLC), MC3 R MC4 R melanocortin agonist, lyophilized solid Sigma Aldrich Melanotan II (Tan Jabs): Why They're Not Worth The Risk Melanotan 1 (10 MG) Sigma Compounds 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 Dangerous 'Barbie drug' Melanotan II sparks crackdown on social media influencers ABC News Melanotan II: Tanning injections, nasal sprays harmful to health