Health expert says Melanotan II darkens skin moles and can make melanoma hard to detect Herald Sun Melanotan II A Sun Kissed Look, and a Confident You. 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' tanning products promoted by influencers To tan or not to tan Atlantic Dermatology & Laser