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ToolsComparePal-GHK vs Pentapeptide-18

Pal-GHK vs Pentapeptide-18

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

Skin & CosmeticAnti-Aging & Longevity
Pal-GHK
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Summary
Pal-GHK is the palmitoylated form of the GHK tripeptide without a copper ion. By conjugating palmitic acid to glycine-histidine-lysine, skin penetration is substantially enhanced, enabling deeper dermal collagen stimulation. It is commonly paired with Pal-GHK-Cu or GHK-Cu in anti-aging formulations.
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
Extended (lipid depot in stratum corneum)
Not applicable (topical)
Admin Route
Topical
Topical
Research
Typical Dose
0.005–0.1% in formulation
0.005–0.05% in formulation
Frequency
Once or twice daily
Twice daily
Key Benefits
  • Stimulates collagen I and III synthesis in dermis
  • Reduces the appearance of fine lines and wrinkles
  • Improves skin elasticity and firmness
  • Inhibits collagenase (MMP-1) to preserve existing collagen
  • Enhances wound healing and skin repair
  • Well-tolerated in anti-aging serums and creams
  • 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
  • Generally very well-tolerated
  • Rare skin irritation at very high concentrations
  • Possible formulation-dependent comedogenicity
  • 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