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 Viral 'Barbie drug' for tanning can cause brain swelling and even cancer, experts warn Liv injected melanotan 2 for two months. It gave her headaches but she felt it was worth it until she found a strange mole. Soon she was diagnosed with stage one melanoma Martina Big, 36, who is from Germany, and her husband Michael Eurwen, 38, who both injected Melanotan, a synthetic hormone to darken their skin have announced that they are planning to permanently