Pentapeptide-18 vs Hexarelin
Side-by-side comparison of key properties, dosing, and research.
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18Growth Hormone Peptides
Hexarelin- Summary
- 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.
- 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.
- Half-Life
- Not applicable (topical)
- ~70 minutes
- Admin Route
- Topical
- SubQ
- Research
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- Typical Dose
- 0.005–0.05% in formulation
- 100–200 mcg
- Frequency
- Twice daily
- 2–3 times daily
- Key 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
- 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
- Side Effects
- Generally very well-tolerated topically
- Rare skin sensitivity or mild irritation
- Theoretical opioid receptor desensitization with very prolonged high-dose use (not documented cosmetically)
- Water retention
- Elevated cortisol
- Elevated prolactin (more pronounced than other GHRPs)
- Receptor desensitization with continuous use
- +1 more
- Stacks With
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