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ToolsCompareRetatrutide vs GHRP-2

Retatrutide vs GHRP-2

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

GLP-1 / Weight Loss Agonists
Retatrutide
Growth Hormone Peptides
GHRP-2
Summary
Retatrutide is an investigational triple receptor agonist targeting GLP-1, GIP, and glucagon receptors simultaneously. Phase 2 trials showed an unprecedented average 24% body weight reduction at 48 weeks — exceeding any approved medication to date. It is in Phase 3 trials as of 2024.
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.
Half-Life
~10–12 days
15–60 minutes
Admin Route
SubQ
SubQ, Intranasal
Research
Typical Dose
0.5 mg → 1 mg → 2 mg → 4 mg → 8 mg → 12 mg
100–300 mcg
Frequency
Once weekly
2–3 times daily
Key Benefits
  • ~24% body weight reduction at 48 weeks in Phase 2 (highest dose)
  • Superior to both semaglutide and tirzepatide in early trial comparisons
  • Triple receptor mechanism addresses multiple obesity pathways
  • Significant reduction in liver fat (MASH/NAFLD indication being studied)
  • Improved cardiovascular and metabolic markers
  • Once-weekly dosing
  • Potential for greatest weight loss of any currently investigated compound
  • 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
Side Effects
  • Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
  • Diarrhea
  • Constipation
  • Heart rate increase (from glucagon receptor agonism)
  • +2 more
  • Increased appetite
  • Water retention
  • Elevated cortisol (modest)
  • Elevated prolactin (modest)
  • +2 more
Stacks With