Disclaimer
CompoundIQ publishes research summaries for informational and educational purposes only. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. Always consult a licensed healthcare provider. Many compounds listed are research chemicals not approved for human use.
MK-677
Also known as: Ibutamoren, Ibutamoren Mesylate, L-163,191, Nutrobal
MK-677 is an orally active, non-peptide growth hormone secretagogue that mimics the action of ghrelin at the GHS-R1a receptor. It significantly increases growth hormone and IGF-1 levels without affecting cortisol. Multiple human clinical trials have demonstrated its efficacy in improving body composition, sleep quality, and bone density.
Risk Level
Medium RiskDifficulty
Beginner| CAS Number | 159752-10-0 |
| Molecular Formula | C27H36N4O5S |
| Class | Peptide |
| Category | Well-Known Peptides |
Mechanism of Action
MK-677 binds to the ghrelin receptor (GHS-R1a) in the hypothalamus and pituitary, stimulating pulsatile GH release that mimics the natural physiological pattern. Unlike exogenous GH, it preserves the hypothalamic-pituitary feedback loop and does not suppress endogenous production. It also increases appetite through ghrelin receptor activation and promotes nitrogen retention.
Dosing Research
Clinical trials have used doses of 10-25 mg orally once daily, typically taken before bed to align with natural GH pulses. The 25 mg dose is most commonly studied. Effects on GH and IGF-1 levels are sustained with continuous use over 12 months or longer.
Side Effects & Risks
Common side effects include increased appetite, water retention, and transient numbness or tingling in extremities. May elevate fasting blood glucose and reduce insulin sensitivity with prolonged use. Lethargy and vivid dreams are frequently reported, and it is contraindicated in individuals with diabetes or insulin resistance.
Research Studies
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Disclaimer
CompoundIQ publishes research summaries for informational and educational purposes only. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. Always consult a licensed healthcare provider. Many compounds listed are research chemicals not approved for human use.