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This is plain-language harm-reduction information, not medical advice. Peptides discussed here are research compounds; most are not approved for human use. People will use them either way — we would rather they have the facts.
What it is
LL-37 is part of the body's innate immune defence. It is produced by skin cells and immune cells in response to infection and is broadly active against bacteria, viruses and fungi.
Used by some researchers for chronic infections, biofilm-driven conditions and as a wound-healing aid.
History
Identified in the 1990s as part of the cathelicidin family of host defence peptides. Decades of basic-science research, growing interest in therapeutic use.
How it works
Disrupts microbial membranes directly. Also modulates immune signalling — recruits and activates immune cells.
Dosage
- Subcutaneous: 100–500 mcg daily for short courses (1–4 weeks).
How it is taken
- Subcutaneous injection. Some protocols use it topically for skin infections or nebulised for respiratory infections.
How to reconstitute
- 5 mg vial with 2 ml BAC water = 2.5 mg/ml. 250 mcg = 10 units on a 1 ml insulin syringe.
How it should arrive
White powder, sealed vial.
How it should look once reconstituted
Clear colourless solution.
What to expect, and when
- Skin / infection effects: typically within days when applicable.
Side effects
- Injection-site irritation and inflammation — LL-37 is itself inflammatory by design.
- Mild flu-like symptoms during early dosing.
Risks
- Long-term safety unknown.
- Sustained immune activation is not benign — short courses are the norm for a reason.
Potential gains
- Broad antimicrobial activity.
- Some support for chronic biofilm-driven infections.
- Anti-inflammatory effects at lower doses.
Other useful information
Not a daily-driver peptide. A targeted tool for specific infection or wound-healing protocols.
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