MK-677
MK-677 (Ibutamoren / Nutrobal)
Oral GH secretagogue — no injections
Muscle GrowthAnti-Aging ★ 78
Half-life
~24 hours (oral)
Cycle
8-24 week cycles, with 4-8 week breaks (to avoid insulin resistance).
Storage
Room temperature, protected from light and moisture.
Research
Phase 2 trials at Merck, investigated for Alzheimer's (development halted 2007)
About
A non-peptide ghrelin receptor agonist in pill form. Raises GH and IGF-1 for 12-24 hours. Popular for those who want GH-related benefits without injections.
Mechanism
Activates ghrelin (GHS-R1a) receptors in the pituitary, triggering a GH pulse similar to hexarelin.
Dosage
10 mg
1x per day (before sleep)
Route
Oral
Duration
8-12 weeks
When to take: Best before sleep — the GH pulse aligns with the natural nocturnal pulse.
Reconstitution
Vial size (mg): Oral (no reconstitution) · BAC water (mL): Not applicable · Concentration: Not applicable
MK-677 comes as capsules or a liquid suspension. The syringe visualizer does not apply.
Benefits
- Raises GH and IGF-1 for 24 hours
- Improved sleep depth
- Increased appetite and muscle mass
- Improved skin and hair
- No injections required
Side effects
- Strong appetite (may be a downside)
- Water retention
- Elevated blood glucose — insulin resistance risk
- Lethargy and fatigue in the first weeks
- Elevated prolactin
Gender notes
Same dose. Popular for bulking.
Cautions
- Diabetes or pre-diabetes
- Active cancer
- Heart failure (water retention)
- Pregnancy and breastfeeding
Research
- Nass et al: MK-677 in older adults
Annals of Internal Medicine · 2008
12-month MK-677 in older adults — sustained GH/IGF-1 elevation.