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ToolsCompareLL-37 vs Pentapeptide-18

LL-37 vs Pentapeptide-18

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

Immune SupportRecovery & Repair
LL-37
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Summary
LL-37 is the only known human cathelicidin antimicrobial peptide. It kills bacteria, fungi, and viruses by disrupting their membranes, while simultaneously modulating immune responses. Used for antimicrobial protection, immune priming, and wound healing.
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
Very short (~1–2 hours) in plasma due to protease degradation; topical use bypasses systemic clearance
Not applicable (topical)
Admin Route
SubQ, Topical, Intranasal
Topical
Research
Typical Dose
100–300 mcg
0.005–0.05% in formulation
Frequency
2–3x per week
Twice daily
Key Benefits
  • Broad-spectrum antimicrobial (bacteria, fungi, viruses)
  • Promotes wound healing and angiogenesis
  • Immune system modulation — enhances innate immunity
  • Reduces LPS-mediated endotoxemia
  • Anti-biofilm activity against resistant organisms
  • Promotes tissue regeneration and keratinocyte migration
  • May protect against sepsis
  • 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
  • Injection site redness and irritation
  • Mild inflammatory response at injection site
  • Potential pro-inflammatory at high doses
  • Rare: fever or flu-like symptoms at initiation
  • 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