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ToolsCompareGHRP-2 vs Pentapeptide-18

GHRP-2 vs Pentapeptide-18

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

Growth Hormone Peptides
GHRP-2
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
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.
Pentapeptide-18 (Leuphasyl) is a synthetic pentapeptide that mimics the sequence of enkephalin, an endogenous neuropeptide. It acts on neuronal pain receptors in facial muscles to reduce muscle contraction intensity and depth of expression lines, functioning similarly to Argireline (Acetyl Hexapeptide-3) but via a different receptor mechanism.
Half-Life
15–60 minutes
Not applicable (topical)
Admin Route
SubQ, Intranasal
Topical
Research
Typical Dose
100–300 mcg
0.005–0.05% in formulation
Frequency
2–3 times daily
Twice 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
  • Reduces depth of expression lines (forehead, crow's feet, glabellar)
  • Inhibits acetylcholine release for muscle-relaxing effect
  • Complementary mechanism to Argireline for enhanced anti-wrinkle activity
  • Reversible and well-tolerated
  • No risk of systemic paralysis at cosmetic concentrations
  • Suitable for daily use in serums and creams
Side Effects
  • Increased appetite
  • Water retention
  • Elevated cortisol (modest)
  • Elevated prolactin (modest)
  • +2 more
  • Generally very well-tolerated topically
  • Rare skin sensitivity or mild irritation
  • Theoretical opioid receptor desensitization with very prolonged high-dose use (not documented cosmetically)
Stacks With