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ToolsCompareLL-37 vs GHK

LL-37 vs GHK

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

Immune SupportRecovery & Repair
LL-37
Skin & CosmeticAnti-Aging & Longevity
GHK
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.
GHK is the natural tripeptide (Gly-His-Lys) released from human albumin that activates tissue remodeling, collagen synthesis, and anti-aging gene expression. The copper-free form is the biological signaling molecule; it chelates copper in tissue to form GHK-Cu but also has independent biological activity.
Half-Life
Very short (~1–2 hours) in plasma due to protease degradation; topical use bypasses systemic clearance
Extremely short as free peptide; tissue binding extends local effects
Admin Route
SubQ, Topical, Intranasal
SubQ, Topical, Oral
Research
Typical Dose
100–300 mcg
100–500 mcg
Frequency
2–3x per week
Daily or 5x per week
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
  • Stimulates collagen and extracellular matrix synthesis
  • Activates tissue repair gene expression programs
  • Anti-aging: reverses 57% of age-related gene changes
  • Antioxidant and anti-inflammatory
  • Wound healing and skin barrier repair
  • Improves skin laxity, texture, and radiance
  • Neuroprotective (stimulates NGF, BDNF)
  • Anti-fibrotic in liver and lung models
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
  • Excellent safety profile (naturally occurring peptide)
  • Rare: mild injection site reaction (SC)
  • No significant adverse effects identified in research
Stacks With