MK-677
Orally active non-peptide ghrelin receptor (GHS-R1a) agonist / growth hormone secretagogue
MK-677 (Ibutamoren) is an orally active growth hormone secretagogue that mimics ghrelin at the GHS-R1a receptor. Despite being grouped with research peptides, it is a small non-peptide molecule taken by mouth rather than injected. It remains investigational and is not an approved drug in the United States.
Mechanism under study
Acts as an agonist at the ghrelin/growth-hormone-secretagogue receptor (GHS-R1a) in the pituitary and hypothalamus, promoting pulsatile release of growth hormone and raising IGF-1 without markedly suppressing endogenous GH regulation. Studied for sustained elevations of GH and IGF-1 and their effects on body composition and bone.
Research-reported dosing
Clinical research has examined oral doses commonly around 10-25 mg once daily, studied over weeks to as long as 1-2 years for body composition and bone endpoints. It is not reconstituted or injected. Investigational; not FDA-approved for any indication.
Not applicable - MK-677 is an orally dosed small molecule, not an injectable peptide, so it is not reconstituted with bacteriostatic water. Research material is typically supplied as a capsule or oral liquid.
Open this mix in the calculator →Dosing figures describe how this compound appears in the research literature and research-community references. They are not a recommendation for human use.
MK-677 comparisons
MK-677 FAQ
What is MK-677?
MK-677 (Ibutamoren) is an orally active growth hormone secretagogue that mimics ghrelin at the GHS-R1a receptor. Despite being grouped with research peptides, it is a small non-peptide molecule taken by mouth rather than injected. It remains investigational and is not an approved drug in the United States.
What is the half-life of MK-677?
Oral; reported plasma half-life on the order of ~4-6 hours, consistent with once-daily dosing in studies, while GH/IGF-1 effects persist longer.
What is the research-reported dosing for MK-677?
Clinical research has examined oral doses commonly around 10-25 mg once daily, studied over weeks to as long as 1-2 years for body composition and bone endpoints. It is not reconstituted or injected. Investigational; not FDA-approved for any indication.
How is MK-677 reconstituted?
Not applicable - MK-677 is an orally dosed small molecule, not an injectable peptide, so it is not reconstituted with bacteriostatic water. Research material is typically supplied as a capsule or oral liquid.
Is MK-677 FDA-approved?
MK-677 has an approved status in at least one context — see the overview above for the specific brand, region, and indication. Research-grade material sold separately is for laboratory use only.
References
Guides featuring MK-677
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