MK-677 (Ibutamoren)
Oral growth hormone secretagogue mimicking ghrelin
🛑 WADA Banned 15 views
🛑 WADA BANNED - Prohibited in competitive sports as growth hormone secretagogue
Overview
MK-677 (Ibutamoren) isn't technically a peptide — it's a small molecule you can take as a pill that mimics ghrelin, your "hunger hormone." The result? Your body produces more growth hormone naturally, without injections. **Why is that significant?** Most growth hormone-releasing compounds require injections. MK-677 is one of the few that works orally, making it much more convenient. One daily dose keeps growth hormone and IGF-1 elevated for 24 hours. **What the research shows:** • Increases growth hormone and IGF-1 levels significantly • May improve sleep quality (GH is released during deep sleep) • Could help preserve muscle mass and bone density • Studied for elderly populations with age-related decline • Does NOT suppress your natural GH production **The trade-off:** Because MK-677 mimics ghrelin, it increases appetite — sometimes significantly. It can also cause water retention and may affect blood sugar in some people. **Clinical research:** Studied in clinical trials for muscle wasting, hip fracture recovery, and growth hormone deficiency, but never received FDA approval. **Important to know:** MK-677 is banned by WADA and not approved for any medical use. Long-term safety data is limited. --- **Sources:** Nass R, et al. (2008) Journal of Clinical Endocrinology & Metabolism | Murphy MG, et al. (1998) Journal of Clinical Endocrinology & Metabolism

Quick Facts
Formula:C28H40N4O5S
Molecular Weight:528.67
Mechanism:Oral ghrelin mimetic and GH secretagogue
⚠️ Safety Information
Research compound only. Not approved for human use.
Research Citations
MK-677, an orally active growth hormone secretagogue, reverses diet-induced catabolism.
Murphy MG, Plunkett LM, Gertz BJ, He W, Wittreich J, Polvino WM, Clemmons DR (1998)
LGD-4033 and MK-677 use impacts body composition, circulating biomarkers, and skeletal muscle androgenic hormone and receptor content: A case report.
Cardaci TD, Machek SB, Wilburn DT, Heileson JL, Harris DR, Cintineo HP, Willoughby DS (2022)
Hepatotoxicity induced by MK-677.
Cobani E, Amin MS, Hasso M, Kumbar L (2025)
+ 42 more citations