Sermorelin vs MK-677 (Ibutamoren)
Side-by-side comparison of key properties, dosing, and research.
Growth Hormone PeptidesAnti-Aging & Longevity
SermorelinGrowth Hormone Peptides
MK-677 (Ibutamoren)- Summary
- Sermorelin is a bioidentical synthetic peptide comprising the first 29 amino acids of naturally occurring GHRH. It is FDA-approved for diagnostic use and widely prescribed off-label for anti-aging, stimulating growth hormone production in a natural pulsatile pattern that mimics the body's own rhythm.
- 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
- 10–20 minutes
- 24 hours
- Admin Route
- SubQ
- Oral
- Research
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- Typical Dose
- 200–500 mcg
- 10–25 mg
- Frequency
- 5–7 days per week
- Once daily
- Key Benefits
- Increases energy and vitality
- Improves body composition (more muscle, less fat)
- Enhances skin thickness and elasticity
- Strengthens immune system
- Improves sleep quality and REM sleep
- Supports bone density
- Enhances mental clarity and focus
- Safer than exogenous HGH — respects natural feedback loops
- FDA-approved for GH diagnostic use
- 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
- Injection site irritation
- Flushing
- Headache
- Dizziness
- +2 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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