Thymulin vs LL-37
Side-by-side comparison of key properties, dosing, and research.
- Summary
- Thymulin is a nonapeptide hormone produced exclusively by the thymic epithelium. It requires zinc for biological activity and plays a critical role in T-lymphocyte maturation, differentiation, and immune regulation. Thymulin levels decline dramatically with age, contributing to immunosenescence.
- 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
- ~30 minutes active half-life
- Very short (~1–2 hours) in plasma due to protease degradation; topical use bypasses systemic clearance
- Admin Route
- SubQ
- SubQ, Topical, Intranasal
- Research
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- Typical Dose
- 20-30 mcg
- 100–300 mcg
- Frequency
- 10 days per month (Khavinson protocol)
- 2–3x per week
- Key Benefits
- Enhances T-cell maturation and differentiation
- Boosts NK cell cytotoxic activity
- Reduces inflammatory cytokine production (TNF-α, IL-1)
- Anti-nociceptive (pain-reducing) properties
- Restores age-related immune decline
- Anti-inflammatory via serotonin pathway modulation
- 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 reactions
- Mild fatigue initially as immune system activates
- 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
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