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 Melanotan 2 (MT II) 99% Pure Nationwide Peptides Your Guide to Melanotan II: What to Know Before Beginning Your Peptide Therapy 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 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 Avoid nasal tanning sprays or nasal tanners entirely. These products promise an all over tan without sun exposure but they are unregulated, can be unsafe, and contain potentially risky substances like Melanotan 2.