Viral 'Barbie drug' for tanning can cause brain swelling and even cancer, experts warn 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 II urgent warning about tanning product pushed on social media news.com.au Australia's leading news site for latest headlines Melanotan II Nasal Tanning Spray Risks: Dizziness, Nausea, Skin Cancer Business Insider Melanotan What It Is and Its Relation to Skin Cancer