At a glance
A human host-defense peptide with antimicrobial and immune-signaling roles.
This profile separates the compound’s scientific background from specification-specific preparation and source schedules. Begin with the research findings and limitations, then select the formulation you want to examine.
How it works
Potential benefits & side effects
Interpret each outcome in the context of the study population, formulation and evidence type. Research findings do not establish a personal treatment outcome.
Potential benefits & research findings
The source discusses antimicrobial experiments and formulation-specific wound studies. Local wound findings should be separated from proposed systemic schedules.[3][4][2]
Read the original publications to see the measured endpoints, comparator, duration and uncertainty. Mechanistic plausibility and a favorable experimental result are different from demonstrated clinical benefit.
Side effects & evidence limitations
Interpret the reported adverse effects together with the study population, route and observation period. Small or short studies can miss uncommon and delayed harms. Evidence from a related compound does not establish the safety of LL-37.
Source-reported adverse effects and cautions
Sources are available for independent reading. Individual claims and research schedules have not yet undergone an independent clinical review by Pep Science.
- Editorial responsibility
- Pep Science editorial desk
- Last independent review
- Not yet recorded
SPECIFICATIONS & SOURCE SCHEDULES
Explore a vial size
Select the exact formulation. Vial content, target dose and prepared concentration are different measurements.
Showing 5 mg · 1 source tables
Standard / Gradual Approach (3 mL = ~1.67 mg/mL)
| Week | Daily Dose (µg) | Units (per injection) (mL) |
|---|---|---|
| Week 1 | 50 µg | 3 units (0.03 mL) |
| Week 2 | 100 µg | 6 units (0.06 mL) |
| Week 3 | 150 µg | 9 units (0.09 mL) |
| Week 4 | 200 µg | 12 units (0.12 mL) |
| Week 5 | 250 µg | 15 units (0.15 mL) |
| Week 6 | 300 µg | 18 units (0.18 mL) |
| Week 7 | 350 µg | 21 units (0.21 mL) |
| Week 8 | 400 µg | 24 units (0.24 mL) |
Frequency: Inject once daily subcutaneously. Some protocols use a 5-days-on, 2-days-off schedule. For ≤10-unit (≤0.10 mL) administrations during early titration, consider 30- or 50-unit insulin syringes for improved readability.
Additional schedule context & duration
Concise summary of the once-daily regimen.
- Goal: Support antimicrobial defense and wound-healing processes[3][4].
- Schedule: Daily subcutaneous injections for 8–12 weeks (extend to 16 weeks if desired).
- Dose Range: 50–400 µg daily with gradual titration.
- Reconstitution: 3.0 mL per 5 mg vial (~1.67 mg/mL) for accurate unit measurements.
- Storage: Lyophilized frozen; reconstituted refrigerated; avoid repeated freeze–thaw.
Suggested daily titration approach.
- Start: 50–100 µg daily; increase by ~50 µg each week as tolerated.
- Target: 200–400 µg daily by Weeks 4–8.
- Frequency: Once per day (subcutaneous); optional 5-on/2-off schedule.
- Cycle Length: 8–12 weeks; optional extension to 16 weeks.
- Timing: Any consistent time; rotate injection sites.
Read this protocol on Pep Science → · View cited documents ↓
Preparation
Reconstitution Steps
- Draw 3.0 mL bacteriostatic water with a sterile syringe.
- Inject slowly down the vial wall; avoid foaming.
- Gently swirl/roll until dissolved (do not shake).
- Label and refrigerate at 2–8 °C (35.6–46.4 °F), protected from light.
Storage Instructions
Proper storage preserves peptide quality[6][5].
- Lyophilized: Store at −20 °C (−4 °F) in dry, dark conditions; stable ~24 months.
- Reconstituted: Refrigerate at 2–8 °C (35.6–46.4 °F) for up to 4 weeks; frozen at −20 °C (−4 °F) for up to 6 months.
- Allow vials to reach room temperature before opening to reduce condensation uptake.
Injection Technique
General subcutaneous guidance from clinical best-practice resources[9].
- Clean the vial stopper and skin with alcohol; allow to dry.
- Pinch a skinfold; insert the needle at 45–90° into subcutaneous tissue[7][10].
- Do not aspirate for subcutaneous injections; inject slowly and steadily[10].
- Rotate sites systematically (abdomen, thighs, upper arms) and move at least 2–3 cm from the previous site[7].
- Use aseptic technique; always use a new sterile needle and syringe for each injection[6].
Materials & quantity planning
Source materials checklist · 5 mg
Plan based on an 8–16 week daily protocol with gradual titration.
-
Peptide Vials (LL-37, 5 mg each):
- 8 weeks ≈ 3 vials
- 12 weeks ≈ 5 vials
- 16 weeks ≈ 7 vials
-
Insulin Syringes (U-100):
- Per week: 7 syringes (1/day)
- 8 weeks: 56 syringes
- 12 weeks: 84 syringes
- 16 weeks: 112 syringes
-
Bacteriostatic Water (10 mL bottles): Use ~3.0 mL per vial for reconstitution.
- 8 weeks (3 vials): 9 mL → 1 × 10 mL bottle
- 12 weeks (5 vials): 15 mL → 2 × 10 mL bottles
- 16 weeks (7 vials): 21 mL → 3 × 10 mL bottles
-
Alcohol Swabs: One for the vial stopper + one for the injection site each day.
- Per week: 14 swabs (2/day)
- 8 weeks: 112 swabs → recommend 2 × 100-count boxes
- 12 weeks: 168 swabs → recommend 2 × 100-count boxes
- 16 weeks: 224 swabs → recommend 3 × 100-count boxes
Calculate a phased quantity
Enter each finite phase from the schedule you are studying. Open-ended phases need an explicit duration. Calculation uses 5 mg per vial and 3 mL per vial.
Complete each phase to calculate totals.
Quantity estimates exclude preparation losses and expiry. Follow the formulation’s handling and disposal requirements.
FOLLOW THE EVIDENCE
References & further reading
Original publications and source documents cited across this product’s variants. A listed source is not an independent endorsement of a dosing schedule.
- 01
Research publication
Journal of Immunology (PMC) — Little peptide, big effects: the role of LL-37 in inflammation and autoimmune disease (opens in a new tab)pmc.ncbi.nlm.nih.gov
Back to overview ↑ - 02
- 05
Source document
Bachem Knowledge Center — Handling and storage guidelines for peptides (opens in a new tab)www.bachem.com
Back to overview ↑ - 06
Public health resource
CDC One & Only Campaign — One needle, one syringe, only one time (injection safety) (opens in a new tab)www.cdc.gov
Back to overview ↑ - 07
Source document
Johns Hopkins Arthritis Center — How to give a subcutaneous injection (site selection, rotation) (opens in a new tab)www.hopkinsarthritis.org
Back to overview ↑ - 08
Research publication
PubMed / Journal of Steroid Biochemistry — Vitamin D and the antimicrobial peptide cathelicidin (LL-37) (opens in a new tab)pubmed.ncbi.nlm.nih.gov
Back to overview ↑ - 09
Public health resource
MedlinePlus (NIH) — Subcutaneous (SQ) injections: patient instructions (opens in a new tab)medlineplus.gov
Back to overview ↑ - 10
Public health resource
CDC — Vaccine administration: subcutaneous injection (angle/site; no aspiration) (opens in a new tab)www.cdc.gov
Back to overview ↑ - 11
Public health resource
NCBI Bookshelf — Best practices for injection (asepsis, preparation, and administration) (opens in a new tab)www.ncbi.nlm.nih.gov
Back to overview ↑ - 12
Research publication
Clinical Pharmacology & Therapeutics (PMC) — Subcutaneous drug injection review: pharmacologic considerations (opens in a new tab)pmc.ncbi.nlm.nih.gov
Back to overview ↑
COMMUNITY · EXTERNAL FORUM
Discuss LL-37 with the community
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