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 2 doesn't just stimulate melanin in your skin, but your hair follicles aswell .. my beard is about 80% darker today, than a month before I started taking melanotan. Guys with Melanotan medAge Aesthetics & Wellness Melanotan II (Tan Jabs): Why They're Not Worth The Risk Melanotan II: Tanning injections, nasal sprays harmful to health