MK-677
MK-677 (ibutamoren) is an orally active non-peptide growth-hormone secretagogue studied to stimulate the GH-IGF-1 axis; research protocols typically use 10 mg orally once daily.
It has been studied as an oral approach to stimulating the GH-IGF-1 axis, with research in healthy older adults, body-composition and lean-mass questions, bone turnover, sleep quality, and conditions involving low GH or muscle wasting.
MK-677 (ibutamoren, developmental code L-163,191) is an orally active, non-peptide growth hormone secretagogue belonging to the spiroindoline chemical class. It is not a peptide; it was engineered as a small-molecule mimetic of the GH-releasing peptides and ghrelin. Research has characterized it as an agonist of the growth hormone secretagogue receptor type 1a (GHS-R1a) — the same receptor activated by the endogenous hormone ghrelin — located in the hypothalamus and pituitary.
Activation has been shown to stimulate pulsatile growth hormone (GH) release and to raise circulating insulin-like growth factor 1 (IGF-1), amplifying the body's physiological GH pulse pattern rather than imposing a sustained surge. Clinical studies have examined its effects on the GH-IGF-1 axis, body composition, bone turnover, and sleep architecture. MK-677 is not FDA-approved for any indication; it is handled as a research compound and is prohibited in sport by WADA.
Research has most commonly used a once-daily oral dose in the 10-25 mg range (25 mg was the dose in the foundational elderly-subject trial), taken consistently because IGF-1 elevation persists for roughly 24 hours after a dose.
Research reports acute GH pulses after a single oral dose, with IGF-1 typically rising into a higher range over the first one to four weeks of daily administration.
In research and informal practice it is often discussed alongside injectable GH secretagogues or GHRH analogs such as CJC-1295 and ipamorelin, though combining secretagogues is not well characterized in controlled studies.
Log every dose, count every vial, and verify your batches — free in the goodtides app.
This page is educational reference material about compounds studied in research settings. It is not medical advice, and nothing here is a recommendation to buy, possess, or use any compound. Research findings described are from published literature; individual compounds may not be approved for human use. Talk to a licensed clinician about anything that affects your health.