Cathelicidin LL-37 · hCAP18
Human antimicrobial peptide — infection, wound healing, immune modulation.
FDA
Research Only
WADA
Not Listed
HALF-LIFE
~3–6 hours
ROUTE
Topical, intranasal, or SubQ injection
SCHEDULE
Daily
In Plain English
Human antimicrobial peptide — infection, wound healing, immune modulation.
Status & Legality
NATTY?
No Test ExistsNo established test exists for this compound.
FDA
Research OnlyFor research purposes only. Not FDA approved.
WADA
Not ListedNot currently on WADA prohibited list.
COMPOUNDING
Not from pharmaciesNot available from licensed compounding pharmacies.
PRESCRIBED
Not prescribedNot prescribed in conventional medicine.
ROUTE
Topical, intranasal, or SubQ injectionAdministration via topical, intranasal, or subq injection.
Wound healing
Antimicrobial
Immune modulation
Biofilm disruption
LL-37 is the only known human member of the cathelicidin family of antimicrobial peptides. It's produced naturally in response to infection and injury. LL-37 disrupts bacterial membranes, modulates immune responses, promotes wound closure, and has shown activity against antibiotic-resistant bacteria including MRSA.
Injection site inflammation
Possible skin irritation (topical)
Flu-like symptoms at high doses
Injecting SubQ for wound healing instead of applying topically at the wound site — topical at the target tissue is far more effective
Using it prophylactically long-term without cycling — reserve for acute infections or active wounds
Combining with high-dose antibiotics without monitoring — additive antimicrobial effects can alter the wound microbiome
Antibiotics — additive antimicrobial effect; generally synergistic for wound care and biofilm disruption
Anti-inflammatory drugs — LL-37 has its own immune-modulatory effects that may compound anti-inflammatory therapy
No established major adverse drug interactions in current literature
LL-37 is the most underutilized antimicrobial peptide in the research space. For chronic wounds or biofilm infections that haven't responded to antibiotics, topical LL-37 is worth exploring. The intranasal route for sinus and respiratory applications is promising but still early-stage in terms of evidence.
Stats
Sources & Studies
Zanetti M., Biochim Biophys Acta, 2004