That quick tan injection is NOT worth the risk., Melanotan peptide injections stimulate pigment cells, and its use has been linked to rapid changes in moles, including the potentially fatal skin Mole vs Freckle How to Tell & When to Get Checked 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 Melanotan What It Is and Its Relation to Skin Cancer JLE European Journal of Dermatology Eruptive naevi and darkening of pre existing naevi 24 h after a single mono dose injection of melanotan II Treating freckles and pigmentation Hope Dermatology