How does MK-677 work?

MK-677, also called ibutamoren, is an oral small molecule, not a peptide. It activates the ghrelin receptor (GHS-R1a), the same receptor ipamorelin uses, and raises growth hormone and IGF-1. Half-life on this site's profile is about 24 hours. Molecular weight is 624.8 daltons. A two-year trial in 65 adults aged 60 to 81 found GH and IGF-1 rose to young-adult levels and fat-free mass increased 1.1 kg versus a 0.5 kg loss on placebo, while strength and function did not improve and fasting glucose and insulin resistance rose. A Phase 2b hip-fracture trial in 123 people was stopped early over a congestive heart failure safety signal. Raising GH is not the same as a measured fat-loss finding. This FAQ does not invent a dose. Full record at /compounds/mk-677.

Educational use only. This database summarizes published research and is not medical advice. Where a dose appears it is a record of what a trial or clinic ran, or what people describe doing, with its source attached. Nothing here is a recommendation for personal use.

Part of growth hormone secretagogues. Sermorelin, tesamorelin, ipamorelin, CJC-1295, and the rest of the GHRH and ghrelin receptor family.