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ToolsComparePentapeptide-18 vs GHK-Cu

Pentapeptide-18 vs GHK-Cu

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

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Skin & CosmeticRecovery & RepairAnti-Aging & Longevity
GHK-Cu
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.
GHK-Cu is a naturally occurring copper complex that declines with age. It is one of the most studied anti-aging peptides, known for powerful skin rejuvenation, wound healing, and tissue remodeling effects.
Half-Life
Not applicable (topical)
2–4 hours
Admin Route
Topical
SubQ, Topical
Research
Typical Dose
0.005–0.05% in formulation
1–3 mg
Frequency
Twice daily
3–5 times per week
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
  • Reduces wrinkles and fine lines
  • Improves skin firmness and elasticity
  • Accelerates wound healing
  • Reduces inflammation and oxidative damage
  • Promotes hair growth and thickness
  • Supports collagen and elastin production
  • May improve overall skin health and appearance
  • Resets aged fibroblast behavior
  • Anti-fibrotic — reduces scar tissue formation
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)
  • Temporary blue-green discoloration at injection site (from copper — harmless)
  • Post-injection sting (brief)
  • Skin irritation with topical use (rare)
Stacks With