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ToolsCompareGHK-Cu vs Pentapeptide-18

GHK-Cu vs Pentapeptide-18

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

Skin & CosmeticRecovery & RepairAnti-Aging & Longevity
GHK-Cu
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Summary
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.
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
2–4 hours
Not applicable (topical)
Admin Route
SubQ, Topical
Topical
Research
Typical Dose
1–3 mg
0.005–0.05% in formulation
Frequency
3–5 times per week
Twice daily
Key Benefits
  • 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
  • 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
  • Temporary blue-green discoloration at injection site (from copper — harmless)
  • Post-injection sting (brief)
  • Skin irritation with topical use (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