Development Stage Phase II
Preclinical
Phase I
Phase II
Phase III
Approved
Phase II: Efficacy & Side effects
Ibutamoren
Also known as: MK-677
Last updated: 1/23/2026 Last reviewed: 1/23/2026
At a Glance
Ibutamoren (MK-677) is a small molecule typically described as a ghrelin receptor (GHSR) agonist that can increase GH/IGF-1 signaling in studied settings. Clinical benefit-risk depends on population and endpoint and is not established for general use.
⚠️ Research Status: This dossier is an intake stub pending literature curation. It is not medical advice. Protocol/dosing guidance is intentionally not included.
Intake Notes (Unreviewed)
- Tags (from internal sheet): Energy; Muscles; Sleep
- Reported half-life (unverified): ~24 hours
- Reported adverse effects (unverified): increased appetite; headache; increased blood sugar/insulin; increased cortisol; sleepiness; edema
Mechanism of Action (TBD)
Candidate target: growth hormone secretagogue receptor (GHSR) (needs primary sources).
Evidence Summary
Low Confidence ReviewLiterature curation pending.
Key Clinical Studies
| Year | PMID | Type | Topic |
|---|---|---|---|
| 2004 | 15298931 | Clinical | Nutritional and hormonal responses |
| 2006 | 16511387 | Clinical | MK-677 clinical study |
Safety & Unknowns
- Metabolic effects (e.g., glucose tolerance) are frequently discussed and require citation-backed characterization.
- Reported adverse effects above are unverified and may not be complete.
Regulatory Status
| Region | Status |
|---|---|
| United States (FDA) | Not approved |
| European Union (EMA) | Not approved |
| WADA | Check current list (status may change) |
Changelog
| Date | Change |
|---|---|
| 2026-01-23 | Added intake stub from compounds sheet |