Overdose of Melanotan II causes muscle breakdown What Happens to Your Body if You Take Too Much Melatonin? 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 Melanotan is not a tan. It's an unregulated peptide with real risk. As a dermatologist, here's the reality: It has been linked to new and changing moles including cases of