MK-677 vs Somatropin
Head-to-head comparison of MK-677 (Ibutamoren Mesylate (MK-677)) and Somatropin (Recombinant human growth hormone (rhGH)) — benefits, dosing, side effects, research data, and where to buy.
Research Score
| Property | MK-677 | Somatropin |
|---|---|---|
| Category | Growth Hormone | Growth Hormone |
| Full Name | Ibutamoren Mesylate (MK-677) | Recombinant human growth hormone (rhGH) |
| Molecular Weight | 528.662 g/mol | 22125 Da |
| Half-Life | ~24 hours | 2-4 hours |
| Amino Acids | Non-peptide compound | 191 |
| Typical Dose | — | 0.004-0.03 mg/kg/day |
| Route | — | Subcutaneous |
| Purity | >99% | ≥98% |
| Studies Count | 120 | 2000 |
| Research Status | Active Research | Clinical/Approved |
MK-677 Benefits
- ✓Oral GH secretagogue, 24-hour GH elevation, increases IGF-1, improves sleep quality, increases lean mass, does not suppress natural GH
Somatropin Benefits
- ✓linear growth support
- ✓lean mass preservation
- ✓bone mineral accrual
- ✓IGF-1 elevation
MK-677 Dosing
10-25 mg orally once daily before bedtime. 25 mg is the most studied dose. Can be used long-term without cycling.
Somatropin Dosing
daily subcutaneous dosing|titrate to IGF-1 and response|weight-based replacement protocols
MK-677 Side Effects
- ⚠Increased appetite, mild water retention, drowsiness, transient numbness, mild increase in fasting blood glucose with long-term use.
Somatropin Side Effects
- ⚠edema
- ⚠arthralgia
- ⚠insulin resistance
Research Overview
MK-677
A landmark 2-year study in elderly adults demonstrated significant increases in lean mass, GH pulsatility, and IGF-1 to youthful ranges. Selectively agonizes GHS-R1a without increasing cortisol or prolactin.
Somatropin
Somatropin is the best-studied growth hormone peptide, with decades of clinical use in pediatric and adult GH deficiency. Trials consistently show increases in IGF-1 and growth velocity, with adverse effects mainly reflecting excessive GH exposure.
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