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ToolsComparePentapeptide-18 vs Tripeptide-29

Pentapeptide-18 vs Tripeptide-29

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

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Skin & CosmeticAnti-Aging & Longevity
Tripeptide-29
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.
Tripeptide-29 is a pro-collagen cosmetic peptide composed of proline, hydroxyproline, and glycine — the core repeating unit of collagen. Applied topically, it signals dermal fibroblasts that collagen degradation has occurred, triggering compensatory new collagen synthesis.
Half-Life
Not applicable (topical)
Not applicable (topical)
Admin Route
Topical
Topical
Research
Typical Dose
0.005–0.05% in formulation
0.01-0.1% 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 fibroblast collagen synthesis via damage-signal mechanism
  • Reduces fine lines and improves skin smoothness
  • Supports dermal matrix integrity
  • Naturally bioidentical to collagen fragment sequences
  • Well-tolerated in all skin types
  • Synergistic with copper peptides and retinoids
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)
  • Excellent tolerability profile
  • No documented significant adverse effects at cosmetic concentrations
  • Rare sensitivity reactions in individuals with peptide allergies
Stacks With