GHRP-6 vs Pentapeptide-18
Side-by-side comparison of key properties, dosing, and research.
Growth Hormone Peptides
GHRP-6Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18- Summary
- GHRP-6 is the original synthetic GH-releasing peptide and a potent ghrelin receptor agonist. It produces strong GH pulses but is notorious for a significant hunger surge 30–45 minutes post-injection. This hunger side effect makes it less preferred than Ipamorelin or GHRP-2 for most protocols but can be useful in patients with appetite deficiency.
- 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
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- Typical Dose
- 100–300 mcg
- 0.005–0.05% in formulation
- Frequency
- 2–3 times daily
- Twice daily
- Key Benefits
- Strong GH stimulation
- Elevated IGF-1
- Muscle growth and recovery support
- Potential anti-inflammatory effects at GI level
- Useful for patients with appetite deficiency or cachexia
- Enhanced recovery from training
- 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
- Intense hunger surge (30–45 min post-injection)
- 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
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