LL-37
LL-37 is the only human cathelicidin antimicrobial peptide. It functions as a first-line immune defense, directly killing bacteria, viruses, and fungi by disrupting their cell membranes. Beyond direct antimicrobial action, LL-37 modulates inflammation, promotes wound healing, and helps recruit immune cells to infection sites. It represents the cutting edge of innate immune support.
Frequency
During illness
Cycle Length
During illness — stop use when feeling healthy.
Route
Subcutaneous
Research Level
Established
Goals
Dosing Protocol
300 mcg to 1 mg per dose, subcutaneous injection. With standard reconstitution (5 mg in 2 mL), 300 mcg = 12 units on a U-100 insulin syringe.
Reconstitution
Add 2 mL bacteriostatic water to a 5 mg vial.
Timing
Morning, on an empty stomach.
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Potential Side Effects
- Injection site pain/redness
- Mild inflammatory response
- Use lower doses initially
Important Warnings
- Can provoke a strong inflammatory response at higher doses
- Use with caution in autoimmune conditions
Works Well With
Research References
- Vandamme D, et al. Cell Immunol. 2012;280(1):22-35. doi:10.1016/j.cellimm.2012.11.009
- Kahlenberg JM, Kaplan MJ. J Immunol. 2013;191(10):4895-4901. doi:10.4049/jimmunol.1302008
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Medical Disclaimer: This information is for educational purposes only and is not intended as medical advice. LL-37 may be regulated differently in various jurisdictions. Always consult with a qualified healthcare provider before beginning any peptide protocol. PepStack Pro does not sell peptides or provide medical advice. Content reviewed by Dr. Seth Miller, MD.