MD breaking down Melanotan II Part 2 of my peptide series. The research, the risks, the reality. Long term safety data? Nonexistent. 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 (Tan Jabs): Why They're Not Worth The Risk Clinically important side effects of Melanotan II and placebo Download Table Viral 'Barbie drug' for tanning can cause brain swelling and even cancer, experts warn Melanotan II is the product that's been dubbed the "Barbie drug" on social media, and promises to give users a tan without the sun but it can have serious side effects including, in rare cases,