PEG-MGF vs MK-677 (Ibutamoren)
Side-by-side comparison of key properties, dosing, and research.
Anabolic & IGF
PEG-MGFGrowth Hormone Peptides
MK-677 (Ibutamoren)- Summary
- PEG-MGF (Pegylated Mechano Growth Factor) is a modified form of MGF (Mechano Growth Factor) where polyethylene glycol (PEG) chains have been attached to extend its half-life from minutes to days. Native MGF is released locally in muscle in response to mechanical stress and quickly degrades. PEGylation allows systemic administration with sustained circulation, enabling whole-body muscle repair and anabolic signaling rather than the purely local effect of native MGF.
- MK-677 (Ibutamoren) is an orally active, non-peptide ghrelin receptor agonist that increases growth hormone and IGF-1 levels. Unlike injectable GHRPs, it can be taken orally and has a 24-hour half-life, making it convenient for sustained GH optimization.
- Half-Life
- ~3 days (due to PEGylation)
- 24 hours
- Admin Route
- SubQ
- Oral
- Research
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- Typical Dose
- 200–400 mcg
- 10–25 mg
- Frequency
- 2–3x per week
- Once daily
- Key Benefits
- Extended half-life (~3 days) vs native MGF (minutes)
- Systemic muscle satellite cell activation via subcutaneous injection
- Promotes muscle fiber repair and hypertrophy throughout the body
- Enhanced recovery from intense training or muscle injury
- Synergistic with IGF-1 LR3 and growth hormone peptides
- Useful in sarcopenia, post-injury recovery, and athletic performance
- Single injection provides multi-day anabolic signaling
- Increases lean muscle mass
- Enhances bone density
- Improves sleep quality and REM sleep
- Accelerates recovery from training
- Increases appetite
- May improve skin elasticity and appearance
- Supports fat loss while maintaining muscle
- Oral administration — no injections required
- 24-hour half-life allows once-daily dosing
- Side Effects
- Water retention and localized swelling
- Potential hypoglycemia at high doses
- Theoretical cancer growth risk (growth factor)
- Injection site reactions
- +1 more
- Increased appetite (significant in some users)
- Water retention and puffiness
- Elevated blood glucose / insulin resistance (monitor in diabetics)
- Lethargy initially
- +2 more
- Stacks With
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