Hexarelin vs MK-677 (Ibutamoren)
Side-by-side comparison of key properties, dosing, and research.
Growth Hormone Peptides
HexarelinGrowth Hormone Peptides
MK-677 (Ibutamoren)- Summary
- Hexarelin is a potent synthetic GHRP and the strongest GH secretagogue in its class per unit dose. It also exhibits unique cardioprotective properties through direct binding to cardiac CD36 receptors, independent of GH release. Its potency is balanced by a tendency to desensitize GH release with prolonged use, making cycling important.
- 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
- ~70 minutes
- 24 hours
- Admin Route
- SubQ
- Oral
- Research
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- Typical Dose
- 100–200 mcg
- 10–25 mg
- Frequency
- 2–3 times daily
- Once daily
- Key Benefits
- Strongest GH pulse per mcg among GHRPs
- Unique direct cardioprotective effects via CD36
- Increased IGF-1 and muscle anabolism
- Accelerated recovery from training
- Bone density support
- Anti-aging via GH axis
- Potential cardiac rehabilitation benefits
- 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
- Elevated cortisol
- Elevated prolactin (more pronounced than other GHRPs)
- Receptor desensitization with continuous use
- +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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