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ToolsComparePentapeptide-18 vs Pal-GHK

Pentapeptide-18 vs Pal-GHK

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

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Skin & CosmeticAnti-Aging & Longevity
Pal-GHK
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.
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.
Half-Life
Not applicable (topical)
Extended (lipid depot in stratum corneum)
Admin Route
Topical
Topical
Research
Typical Dose
0.005–0.05% in formulation
0.005–0.1% in formulation
Frequency
Twice daily
Once or twice 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
  • 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
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)
  • Generally very well-tolerated
  • Rare skin irritation at very high concentrations
  • Possible formulation-dependent comedogenicity
Stacks With