LL-37
Antimicrobial
The body's broad spectrum antimicrobial peptide.
Also sold as
Research chemical vendors can't legally label products with the real name, so LL-37 often appears under coded SKUs. If you're shopping and see any of these, it's the same compound:
- LL37
- Cathelicidin
Codes shown are for identification only.
Your draw
What it actually is
The active C terminal fragment of human cathelicidin. Disrupts bacterial, viral, and fungal membranes and modulates the innate immune response. Levels are often low in chronic infection.
Why people use it
- Chronic biofilm infections that don't clear with antibiotics
- Lyme, mold illness, and stealth pathogen protocols
- Acne and resistant skin infections
Educational only · Not a vendor claim
How it works
Active fragment of human cathelicidin — disrupts microbial membranes and tunes innate immunity.
Health benefits
- Broad antimicrobial effect
- Biofilm disruption
- Modulates innate immunity
What you'll feel
- Symptom improvement in chronic infection
- Reduced skin breakouts
- Energy lift in stealth infection cases
Pros
- Works where antibiotics fail
- Active vs. bacteria, viruses, fungi
- Strong biofilm activity
Cons
- Herxheimer style flares possible
- Cycling required
- Not for autoimmune dominance
Side effects to know
- Die off symptoms early on
- Headache and fatigue
- Mild injection site irritation
Best suited for
Educational summary · Not medical advice · Discuss with a qualified clinician
Typical timeline
General pattern for the Immunity category. Individual response varies.
- Week 1Subtle. Sleep may improve as inflammation drops.
- Weeks 2–4Fewer minor infections, better recovery from training or travel stress.
- Post-cycleBenefits carry for weeks. Bioregulator-style cycles (20–30 days on, then off) are typical.
Pairs well with
Common combinations experienced users run alongside LL-37. Always add one peptide at a time so you can attribute effects and side effects.
Read the safety guide before stacking.
The reconstitution math
- 1Reconstitute the 10 mg vial with 4 mL of bacteriostatic water. Tilt — don't shake.
- 2Concentration becomes 2,500 mcg/mL (2.5 mg/mL).
- 3For a 125 mcg dose, draw 0.050 mL — that's 5 units on a 1 mL insulin syringe.
- 4One vial gives you approximately 80 doses.
Reminder: 100 units on an insulin syringe = 1 mL. Always start at half the listed dose for the first week and rotate injection sites between arms, legs, abdomen, and glutes.
Dose logging is available for signed-in users. Track today's dose and notes for LL-37.
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Mixing ratios, units to draw and storage basics — one page, no strings.
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Keep going from here
Everything on the site that connects to LL-37: comparable compounds, the exact math for this vial, and the tools to run the cycle.
Compare with these
Tools for this protocol
Prefilled with 10 mg, 4 mL BAC water, and a 125 mcg dose.
Printable units-to-micrograms lookup for every common vial and water volume.
Add LL-37 to a protocol with schedule, dosing, and a shopping list.
Log each dose so you can tie effects and side effects to real dates.
Put LL-37 next to two other peptides on dosing and goals.
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