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ToolsCompareHexarelin vs Pentapeptide-18

Hexarelin vs Pentapeptide-18

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

Growth Hormone Peptides
Hexarelin
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
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.
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
~70 minutes
Not applicable (topical)
Admin Route
SubQ
Topical
Research
Typical Dose
100–200 mcg
0.005–0.05% in formulation
Frequency
2–3 times daily
Twice 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
  • 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
  • Water retention
  • Elevated cortisol
  • Elevated prolactin (more pronounced than other GHRPs)
  • Receptor desensitization with continuous use
  • +1 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