Gonadorelin vs MK-677 (Ibutamoren)
Side-by-side comparison of key properties, dosing, and research.
Sexual Health & LibidoAnti-Aging & Longevity
GonadorelinGrowth Hormone Peptides
MK-677 (Ibutamoren)- Summary
- Gonadorelin is the synthetic form of endogenous GnRH (gonadotropin-releasing hormone). It stimulates the pituitary to release LH and FSH, maintaining testicular function and testosterone production. Widely used alongside TRT to prevent testicular atrophy and preserve fertility.
- 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
- ~2–4 minutes (extremely short); pulsatile dosing required to avoid desensitization
- 24 hours
- Admin Route
- SubQ, Intranasal
- Oral
- Research
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- Typical Dose
- 100 mcg
- 10–25 mg
- Frequency
- Twice daily (every 12 hours)
- Once daily
- Key Benefits
- Maintains testicular size during TRT
- Preserves fertility and sperm production during testosterone use
- Stimulates endogenous LH/FSH production
- Maintains HPG axis function during exogenous hormone use
- Used for HCG-free TRT protocols
- Helps restart natural testosterone production (PCT)
- 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 reactions
- Headache
- Nausea at initiation
- Tachycardia (rare)
- +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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