Comparison
While Ipamorelin is investigated for producing moderate, physiologic-like GH pulses useful for studying anabolic, body-composition, and recovery effects with a relatively clean endocrine side-effect profile compared with earlier GHRPs16, Melanotan I is approved in some regions for prevention of phototoxicity in erythropoietic protoporphyria and is studied as a skin-darkening, photoprotective peptide3444.
While Ipamorelin works as a third-generation pentapeptide growth hormone secretagogue that selectively agonizes the ghrelin (GHSR-1a) receptor to trigger controlled, GH-specific pituitary release with minimal effects on cortisol or prolactin16269596, Melanotan I is a linear 13-amino-acid analog of α-MSH (afamelanotide) that selectively activates MC1R on melanocytes, increasing eumelanin synthesis and providing photoprotection3444.
Ipamorelin is 5 amino acids long, whereas Melanotan I is longer as it has a length of 13 amino acids. Ipamorelin is made up of a sequence of Aib, Histidine, D-2-Nal, Phenylalanine, Lysine. Melanotan I is made up of a sequence of Serine, Tyrosine, Serine, Nle, Glutamic acid, Histidine, Phenylalanine, Arginine, Tryptophan, Glycine, Lysine, Proline, Valine.
Ipamorelin
GHSR
Melanotan I
POMC