Melanotan Erectile Dysfunction: What the Early Research Shows and Practical Considerations Melanotan 2 Injectable Peptide How long until peptides actually start working? The #1 question from anyone starting peptides: Should I be feeling something already? Truth: biology doesn't skip steps. Some compounds hit receptors that fire 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 Children's Sleep Liquid with Melatonin Zarbee's