Melanotan II Nasal Tanning Spray Risks: Dizziness, Nausea, Skin Cancer Business Insider Health Check: why does hair change colour and turn grey? : Find an Expert : The University of Melbourne Melanotan II (Tan Jabs): Why They're Not Worth The Risk 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 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