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ToolsCompareIpamorelin vs Pentapeptide-18

Ipamorelin vs Pentapeptide-18

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

Growth Hormone Peptides
Ipamorelin
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Summary
Ipamorelin is a selective GHRP (growth hormone releasing peptide) and one of the cleanest GH secretagogues available. It selectively stimulates GH release without significantly raising cortisol, prolactin, or appetite — making it ideal for long-term use and anti-aging protocols.
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
2 hours
Not applicable (topical)
Admin Route
SubQ
Topical
Research
Typical Dose
100–300 mcg
0.005–0.05% in formulation
Frequency
Once to twice daily
Twice daily
Key Benefits
  • Increases lean muscle mass
  • Enhances fat loss
  • Improves recovery time
  • Strengthens bones and joints
  • Better sleep quality and REM sleep
  • Enhanced skin elasticity
  • Minimal impact on hunger or cortisol
  • No cortisol or prolactin spike
  • Clean GH release suitable for long-term protocols
  • 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
  • Injection site irritation
  • Temporary water retention (mild)
  • Possible hunger increase (milder than GHRP-6)
  • Numbness or tingling in extremities (rare)
  • 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