MK 677 vs Ipamorelin: Which Peptide Reigns Supreme for Muscle Growth? In the fitness industry, MK 677 is often discussed as a growth hormone secretagogue a compound that encourages your body to release more of its own growth hormone., Why does this matter?, Better MK 677 Dripps Ipamorelin Did You Know? Ipamorelin is a peptide classified as a growth hormone secretagogue, studied for its interaction with the ghrelin receptor (GHS R1a). Researchers examine how this pathway influences controlled Best Peptides for Recovery: BPC 157, TB500, MK 677 & More Out with the Old & In with the New: FDA Bans Some Peptides (includes easy reference table)