LL-37 (Cathelicidin)
LL-37 is the only human cathelicidin antimicrobial peptide. It plays crucial roles in innate immunity and has shown diverse biological activities including antimicrobial, immunomodulatory, and wound healing properties.
Mechanism of Action
Disrupts bacterial membranes, neutralizes endotoxins, modulates immune cell function, and promotes wound healing. Has both direct antimicrobial and immunomodulatory effects.
Dosage Overview
Dose Range
500 mcg – 1.6 mg
Route
topical
Frequency
1x daily
Cycle Length
2–4 weeks
Reconstitution
Typical Dosage (Research)
Research protocols vary widely. Typical ranges: 50-200mcg administered subcutaneously 2-3 times weekly. Some protocols use higher doses for acute infections.
Subcutaneous injection. Can cause significant injection site reactions. Often used in conjunction with other immune-supporting protocols.
Considerations for Men & Women
Women: Antimicrobial peptide (cathelicidin). Primarily topical use. No established sex-specific differences in antimicrobial or wound-healing effects. May be beneficial for hormonal acne in women when used topically.
Men: Same antimicrobial profile. Topical application for wound healing and skin conditions. No sex-specific considerations.
Individual responses vary. These notes reflect general trends from research literature and are not medical advice.
Quick Calculator
Quick Calculator
Concentration: 2,500 mcg/ml
Volume to inject: 0.20 ml
Syringe units (U-100): 20.0 units
Pre-filled with LL-37 (Cathelicidin) defaults. Adjust values as needed.
Side Effects & Risks
Injection site pain and reactions are common. May cause flu-like symptoms, temporary fatigue, or immune activation responses.
May overstimulate immune system in autoimmune conditions. Limited human research data. Quality and purity concerns with research products.
Where to Buy LL-37 (Cathelicidin)
All Vendor Details →US-based vendor with third-party HPLC testing and published COAs. One of the few reputable sources we've verified for research-grade peptides.
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Finnrick grades are based on independent HPLC lab testing. Learn more · Finnrick is a commercial service — ratings are third-party, not independent.
Who Uses LL-37 (Cathelicidin)
Those seeking antimicrobial support, individuals with chronic infections, biohackers focused on immune optimization.
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