Melanotan II: Before And After Tan, Bodybuilding 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 Figure 4 from Changes of melanocytic lesions inducedby Melanotan injections and sun bed use ina teenage patient with FAMMM syndrome Semantic Scholar Maintaining Tan with Melanotan 1: Dosage, Results, and Differences from Melanotan 2