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.
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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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