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ToolsCompareGHRP-2 vs MK-677 (Ibutamoren)

GHRP-2 vs MK-677 (Ibutamoren)

Side-by-side comparison of key properties, dosing, and research.

Growth Hormone Peptides
GHRP-2
Growth Hormone Peptides
MK-677 (Ibutamoren)
Summary
GHRP-2 is a potent synthetic hexapeptide that stimulates growth hormone release by activating ghrelin receptors in the pituitary and hypothalamus. It produces one of the strongest GH pulses among GHRPs, though unlike Ipamorelin it does cause modest increases in cortisol and prolactin.
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
15–60 minutes
24 hours
Admin Route
SubQ, Intranasal
Oral
Research
Typical Dose
100–300 mcg
10–25 mg
Frequency
2–3 times daily
Once daily
Key Benefits
  • Strong GH pulse stimulation
  • Increased IGF-1 levels
  • Enhanced muscle growth and recovery
  • Improved fat metabolism
  • Better sleep quality
  • Increased bone density
  • Enhanced appetite (less pronounced than GHRP-6)
  • Anti-aging effects via GH axis optimization
  • 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
  • Increased appetite
  • Water retention
  • Elevated cortisol (modest)
  • Elevated prolactin (modest)
  • +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