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ToolsCompareSermorelin vs LL-37

Sermorelin vs LL-37

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

Growth Hormone PeptidesAnti-Aging & Longevity
Sermorelin
Immune SupportRecovery & Repair
LL-37
Summary
Sermorelin is a bioidentical synthetic peptide comprising the first 29 amino acids of naturally occurring GHRH. It is FDA-approved for diagnostic use and widely prescribed off-label for anti-aging, stimulating growth hormone production in a natural pulsatile pattern that mimics the body's own rhythm.
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.
Half-Life
10–20 minutes
Very short (~1–2 hours) in plasma due to protease degradation; topical use bypasses systemic clearance
Admin Route
SubQ
SubQ, Topical, Intranasal
Research
Typical Dose
200–500 mcg
100–300 mcg
Frequency
5–7 days per week
2–3x per week
Key Benefits
  • Increases energy and vitality
  • Improves body composition (more muscle, less fat)
  • Enhances skin thickness and elasticity
  • Strengthens immune system
  • Improves sleep quality and REM sleep
  • Supports bone density
  • Enhances mental clarity and focus
  • Safer than exogenous HGH — respects natural feedback loops
  • FDA-approved for GH diagnostic use
  • 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
Side Effects
  • Injection site irritation
  • Flushing
  • Headache
  • Dizziness
  • +2 more
  • 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
Stacks With