You Should Avoid Using Nasal Tanning Sprays Melanotan II (acetate) (MT II) Cayman Chemical Melanotan I acetate 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 Melanotan peptide might seem like the cool thing to doit makes you look tan., But these unregulated injections come with real risks., They can cause unpredictable skin changes, including darkening of