MK-677: Benefits, Dosage & FDA Status
Ibutamoren (MK-677)
An orally active ghrelin-receptor agonist that drives 24-hour increases in GH and IGF-1. Technically a non-peptide small molecule but always grouped with GH peptides.
FDA Status
Not FDA-approved — investigational (orally active GH secretagogue)
Typical Dose
10–25 mg orally, once daily
Evidence Grade
B+Multiple clinical studies + widespread clinical use
Half-Life
~6 hours
Routes of Administration
oral
First Synthesized
1995
Clinics Indexed
165 providers have offered MK-677 in our tracked directory.
Mechanism of Action
Small-molecule ghrelin (GHS-R1a) receptor agonist with high oral bioavailability; produces sustained GH and IGF-1 elevation.
Key Reported Benefits
- ✓Sustained GH/IGF-1 elevation
- ✓Sleep depth
- ✓Lean mass
- ✓Bone density
Benefits listed reflect commonly reported effects from clinical trials and practitioner use. Individual response varies. Evidence-grade B+ indicates multiple clinical studies + widespread clinical use.
Reported Side Effects
- •Increased appetite
- •Water retention
- •Muscle pain
- •Insulin resistance with chronic use
Contraindications
- ⚠Diabetes
- ⚠Heart failure (fluid retention)
- ⚠Active malignancy
- ⚠Pregnancy
Regulatory & Safety Context
FDA status: Not FDA-approved — investigational (orally active GH secretagogue)
This page is for educational purposes only and does not constitute medical advice. Peptide use outside of an FDA-approved indication should be discussed with a licensed medical professional. Source quality, cold-chain storage, and injection hygiene all materially affect safety outcomes.
See state-by-state legality: US peptide legality by state →
References
Selected primary literature on MK-677. Full PubMed records linked. Additional citations are available on request.
Last reviewed: 2026-04-30
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