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 Hannah Tittensor and her boyfriend Ben Dunlop have been injecting themselves with an illegal tanning drug called Melanotan for three years. On top of that, they use sunbeds regularly and slather themselves Melanotan What It Is and Its Relation to Skin Cancer 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