MK-677 (Ibutamoren) vs Sermorelin
A side-by-side research comparison of MK-677 (Ibutamoren) and Sermorelin across mechanism, dosing, half-life, benefits, side effects and research status.
Comparison table
| Attribute | MK-677 (Ibutamoren) | Sermorelin |
|---|---|---|
| Full name | Ibutamoren Mesylate (MK-677) | Sermorelin Acetate (GHRH 1-29) |
| Category | Growth Hormone | Growth Hormone |
| Status | Investigational | Previously FDA-approved (discontinued 2008) |
| Mechanism | Acts as ghrelin mimetic at GHS-R1a receptors in hypothalamus and pituitary. Excellent oral bioavailability and 24-hour duration. | Binds GHRH receptors on anterior pituitary via cAMP-PKA pathway. Preserves natural feedback regulation and pulsatility unlike exogenous HGH. |
| Molecular weight | 528.7 Da | 3,358 Da |
| Half-life | 24 hours | 10-20 minutes |
| Bioavailability | High (oral) | Moderate (SubQ) |
| Typical dose | 10-25 mg | 200-300 mcg |
| Frequency | Once daily | Once daily before bed |
| Route | Oral (capsule/liquid) | Subcutaneous injection |
MK-677 (Ibutamoren) reported benefits
- Oral administration
- Sustained 24h GH elevation
- Increased IGF-1
- Improved sleep depth
- Enhanced recovery
- Bone density support
Sermorelin reported benefits
- Natural GH pulsatility preserved
- Improved sleep quality
- Body composition improvement
- Skin elasticity
- Long safety record
Related comparisons
Research and educational reference only. Not medical advice.