The Last Neuroscientist Andrew Huberman warns about the dangers of Melanotan II, a synthetic tanning peptide allegedly used by Robert F Kennedy Jr, due to its potential complications and side effects. >> 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 Day 4: Whacky Side Effects. , I am cutting back from daily use and probably using once a week from here on out. , Zero appetite, Fatigue, And what I think was sleep paralysis , And yes Pyoderma Gangrenosum Secondary to Melanotan Cureus