LL-37 (5 mg vial)
Once daily subcutaneous protocol for tissue-repair research.
LL-37 is the human cathelicidin, an antimicrobial peptide of the innate immune system studied for biofilm disruption and immune modulation. Dosing tolerance varies, so the protocol below escalates very slowly from a small subcutaneous starting dose.
Quick answer: at the standard 5 mg + 0.5 mL reconstitution, a 400 mcg dose of LL-37 draws 4 units (0.04 mL) on a U-100 insulin syringe, once daily subcutaneous.
Protocol overview
Dosing & reconstitution
Frequency: Once daily subcutaneous
Typical duration: 8-12 weeks
Reconstitution: 5 mg vial + 0.5 mL bacteriostatic water = 10 mg/mL. Units below are for a U-100 insulin syringe at this concentration.
| Phase | Dose | Units per injection |
|---|---|---|
| Week 1 | 50 mcg | 0.5 units (0.005 mL) |
| Week 2 | 100 mcg | 1 unit (0.01 mL) |
| Week 3 | 150 mcg | 1.5 units (0.015 mL) |
| Week 4 | 200 mcg | 2 units (0.02 mL) |
| Week 5 | 250 mcg | 2.5 units (0.025 mL) |
| Week 6 | 300 mcg | 3 units (0.03 mL) |
| Week 7 | 350 mcg | 3.5 units (0.035 mL) |
| Week 8 | 400 mcg | 4 units (0.04 mL) |
Units = (dose ÷ concentration) × 100 on a U-100 syringe. Change the vial size or water volume and the calculator redoes all of this for you.
Track this protocol → Free account · log doses, rotate sites, never lose your history
LL-37 dosing — what the literature actually supports
We publish a schedule when there is a citable human source and we say so when there is not. Filling this space with a number nobody measured would make the page look more complete and be worth less than nothing to you.
Reconstitution and measurement
This part is arithmetic and does not depend on the evidence level. Concentration is vial size divided by the bacteriostatic water you add. Draw volume is your target amount divided by that concentration. Units are draw volume times 100, because a U-100 syringe reads 100 units per millilitre. Common vials for LL-37: Not stocked by our featured supplier.
- Wipe the stoppers of both vials with an alcohol swab and let them dry.
- Draw the bacteriostatic water with a sterile syringe and inject it slowly down the inside wall of the peptide vial — never straight onto the powder.
- Swirl gently until the solution is clear. Do not shake; foaming and agitation damage peptides.
- Label the vial with the date and concentration, and refrigerate at 2–8 °C protected from light.
Storage and stability
Important notes
Practical considerations for consistency and safety.
- Use a new sterile insulin syringe for each injection and dispose in a proper sharps container.
- Inject slowly and steadily; wait a few seconds before withdrawing the needle to ensure complete delivery.
- Administer at the same time each day for consistent levels. Setting a daily reminder helps maintain the schedule.
- This compound lacks controlled human safety data. Start with the lowest reported amount and increase gradually while monitoring for any adverse reactions.
- The 5 mg vial size is standard for this compound. Reconstitute with 0.5 mL bacteriostatic water for a convenient concentration.
How LL-37 works
The only human cathelicidin-derived antimicrobial peptide. It has direct antimicrobial activity and a broad immunomodulatory role, and is studied in wound healing and infection.
Benefits & side effects
Potential benefits
- Human antimicrobial peptide with immune modulation
- Supports innate immune defence
- Anti-biofilm properties reported in research
- Promotes wound healing in models
Possible side effects
- Very slow escalation needed to assess tolerance
- Injection site reactions
- Potential for immune activation at higher doses
- Limited human safety data
This list reflects published literature and community reports. Individual responses vary. Not medical advice.
Bloodwork worth tracking
The community-standard practice is a baseline panel before starting, a recheck 8 to 12 weeks in, and another after time off. For LL-37, the markers most worth watching:
CMPCBC with differentialCRP
Typical time off: 4 wks
Lab panels are how a research protocol stays honest: numbers move before symptoms do. Interpretation belongs with a clinician. Not medical advice.
Lifestyle factors
None of the literature above was run on a background of poor sleep and no protein. These variables move outcomes more reliably than any compound on this site.
- Protein in the 1.6 to 2.2 g/kg range preserves lean mass through any body-composition phase.
- Resistance training 2 to 4 days per week plus 150+ minutes of weekly aerobic work reinforces whatever the protocol is doing.
- Sleep is the recovery window: 7 to 9 hours at consistent times.
- Hydration matters more than usual on compounds with GI or flushing effects: 2 to 3 liters daily.
- Track the variables that matter: weigh-ins, measurements, photos, and labs at sensible intervals.
References
Quick answers
How many syringe units is a 400 mcg dose of LL-37?
At the standard reconstitution of 5 mg with 0.5 mL bacteriostatic water (10 mg/mL), a 400 mcg dose draws 4 units (0.04 mL) on a U-100 insulin syringe.
How do you reconstitute LL-37?
Add 0.5 mL of bacteriostatic water to the 5 mg vial for 10 mg/mL. Inject the water slowly down the inside wall of the vial, swirl gently without shaking, and refrigerate at 2 to 8 °C after mixing.
How long does a 5 mg vial of LL-37 last?
About 12 maintenance doses of 400 mcg, roughly 1.7 weeks at once daily subcutaneous.
Does LL-37 have human trial data?
No. The evidence base is animal and cell studies; the practical dosing shown is community convention, and the page labels it that way.
How does LL-37 work?
The only human cathelicidin-derived antimicrobial peptide. It has direct antimicrobial activity and a broad immunomodulatory role, and is studied in wound healing and infection.
Sourcing LL-37
Our featured supplier does not stock this compound, and we are not going to point you at a vendor we have not looked at. Use the COA checklist on whoever you do buy from, and check the batch number on the certificate against the vial you receive.
