2013 · FINDING
Duplantier & van Hoek — antimicrobial
Review: LL-37 active against MRSA, E. coli, Candida, P. aeruginosa including biofilms.
⚠ RESEARCH USE ONLY · NOT FDA-APPROVED FOR HUMAN USE · NOT MEDICAL ADVICE
IMMUNERESEARCH
LL-37.
Your body's natural antibiotic — in a vial
AKA · Cathelicidin · CAMP-derived peptide
IMMUNEHEALINGSUBCUTANEOUSTOPICAL
LL-37 is the only human member of the cathelicidin antimicrobial peptide family. It kills bacteria, fungi, and viruses directly while also modulating immune responses. A serious compound with serious tradeoffs.
~1 hour (free) / extended in tissue
Half-life
3
Citations
2
Routes
2
Categories
68
Popularity
AT A GLANCE.
§ 01 · TL;DRTHE QUICK READ.
LL-37 is the only human member of the cathelicidin antimicrobial peptide family. It kills bacteria, fungi, and viruses directly while also modulating immune responses. A serious compound with serious tradeoffs.
Punches holes in microbial cell membranes. Also tells your immune system to amp up the appropriate response.
Short cycles. Not for chronic autoimmune conditions.
WHAT IT MIGHT HELP WITH.
1
Broad-spectrum antimicrobial activity
2
Active against biofilm-forming bacteria
3
Modulates immune responses (pro- or anti-inflammatory depending on context)
4
Wound healing support in chronic wounds
5
Investigated for antibiotic-resistant infections
HOW IT WORKS.
§ 02 · MECHANISMPunches holes in microbial cell membranes. Also tells your immune system to amp up the appropriate response.
37-residue α-helical amphipathic cationic peptide. Disrupts negatively charged microbial membranes via carpet/toroidal pore formation. Secondary immunomodulatory effects via FPR2 receptor activation influence monocyte, neutrophil, and T-cell recruitment.
WHO IT'S FOR
- ✓Antimicrobial research
- ✓Chronic biofilm infection models
WHO SHOULD AVOID
- ✕Psoriasis
- ✕Lupus / autoimmune conditions
- ✕Pregnancy
THE RESEARCH.
§ 03 · 3 STUDIES2008 · FINDING
Carretero et al. — wound healing
Topical LL-37 accelerated closure of chronic venous leg ulcers in Phase II.
2007 · FINDING
Lande et al. — autoimmunity
LL-37 complexes with self-DNA drive plasmacytoid DC activation in psoriasis.
DOSING PROTOCOL.
§ 04 · DOSINGTYPICAL RANGE
Short cycles. Not for chronic autoimmune conditions.
100–500mcg subcutaneous, 2–3x weekly (highly variable)
FREQUENCY
Most-cited schedule
Intermittent — not daily
ROUTES
Delivery methods
SUBCUTANEOUS · TOPICAL
HALF-LIFE
Steady state drives frequency
~1 hour (free) / extended in tissue
⚠ NOTE
These are reported protocols from research literature and practitioner accounts, not prescriptions. No FDA-approved human dose exists for research compounds. Anyone using LL-37 should work with a qualified physician and source from a supplier providing third-party COAs.
FORMS AVAILABLE
- · Lyophilized vial, 5mg typical
⚠ RESEARCH INFORMATION ONLY · NOT MEDICAL ADVICE
SIDE EFFECTS & RISKS.
§ 06 · SAFETY·
Injection site reactions
Common · mild
•
Transient flu-like symptoms
Reported · moderate
Immune activation
!
Hemolysis at high doses
Dose-dependent · serious
!
Potential autoimmune flare
Theoretical · serious
LL-37 is implicated in psoriasis/lupus pathology
WHERE TO SOURCE
§ 07 · SUPPLIERPEAK LAB
PEPTIDES
PEPTIDES
SUPPLIER OF RECORD · 12 BATCHES PASSED
We tried nine suppliers across 2025 and kept picking PEAK LAB for LL-37: 99.4% HPLC purity, COA on every batch, cold chain intact. Shop through our link and we earn a small commission — affiliate relationship is disclosed.
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