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ToolsComparePentapeptide-18 vs Palmitoyl Dipeptide-6

Pentapeptide-18 vs Palmitoyl Dipeptide-6

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

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Skin & CosmeticAnti-Aging & Longevity
Palmitoyl Dipeptide-6
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.
Palmitoyl Dipeptide-6 is a synthetic dipeptide (lysine-threonine) with a palmitoyl fatty acid tail, designed to penetrate the skin barrier and stimulate the extracellular matrix components essential for skin firmness. It activates fibronectin and type IV collagen synthesis, improving skin density and firmness particularly in mature or sagging skin.
Half-Life
Not applicable (topical)
Not applicable (topical)
Admin Route
Topical
Topical
Research
Typical Dose
0.005–0.05% in formulation
0.005–0.05% 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
  • Increases skin firmness and density
  • Stimulates fibronectin and collagen IV production
  • Strengthens the dermal-epidermal junction
  • Reduces skin sagging in mature skin
  • Improves skin texture and smoothness
  • Supports extracellular matrix integrity
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 well-tolerated
  • Rare mild skin irritation in sensitive individuals
  • No known systemic effects at cosmetic concentrations
Stacks With