LL-37
Also known as: Cathelicidin, CAMP, hCAP-18
LL-37 is the only human cathelicidin, a natural antimicrobial peptide with broad-spectrum activity. It plays a crucial role in innate immunity and wound healing.
Beginner Basics
Plain-English guide to LL-37
What it does
LL-37 is a natural infection-fighting protein your body already makes. Researchers study it because it kills a wide range of bacteria and viruses, reduces inflammation, and helps wounds heal faster.
Typical dose
Researchers typically use 5-10 mg injected under the skin or into muscle, 2-3 times per week.
When to inject
Most commonly used when dealing with illness or infection, or during periods when immune support is needed-there's no specific time of day requirement.
Storage
Keep the dry powder in the refrigerator. Once you mix it with liquid, store it in the fridge and use it within the timeframe specified on your vial.
First-timer tip
This peptide works best when used in cycles rather than continuously, so plan breaks between usage periods to let your body respond naturally.
On This Page
Research Status
Research compound
For research purposes only. Not approved for human use. Not medical advice.
Research Areas
Side Effects
Localized erythema, mild pain, or transient swelling at the injection site typically resolves within 24 hours. Rotate injection sites to minimize recurrence. Apply ice if needed for comfort.
May occur 2–6 hours post-injection as part of normal immune activation. Typically self-resolving within 12–24 hours. Stay hydrated and monitor temperature.
Mild headache may occur within hours of injection. Usually resolves without intervention; over-the-counter analgesics may be used if needed.
Transient tiredness or general malaise may occur as part of immune system activation. Typically resolves within 24–48 hours. Ensure adequate rest and hydration.
Mild nausea has been reported in some users. Usually self-resolving. Avoid heavy meals immediately before or after injection.
Repeated injections at the same site can cause localized fat loss (lipoatrophy) or fat accumulation (lipohypertrophy). Strict site rotation prevents this. If lipodystrophy develops, discontinue injections at that site and allow 4–8 weeks recovery.
Allergic reactions including urticaria, angioedema, or anaphylaxis are rare but possible. Seek immediate medical attention if difficulty breathing, throat swelling, or severe rash occurs. Discontinue use and do not re-inject.
In rare cases, excessive immune stimulation may occur, particularly with high doses or frequent injections. Symptoms may include prolonged fever, severe fatigue, or lymphadenopathy. Reduce dose or frequency and consult a healthcare provider.
Dosing Reference
| Parameter | Value |
|---|---|
| Dose range | 5-10 mg |
Frequency, timing and route - members only | |
Research disclaimer
Figures drawn from published research literature and community logs. Not clinical recommendations. Consult a qualified professional. Research use only.
Reconstitution Guide
Do not use saline or bacteriostatic saline, use only bacteriostatic water for reconstitution
Do not shake the vial vigorously; gentle swirling prevents peptide degradation
Discard immediately if the solution appears cloudy, discolored, or contains visible particles
Use within 30 days of reconstitution when stored at 2-8°C
Do not freeze the reconstituted solution; freezing may denature the peptide
Use the PeptideVolt reconstitution calculator for your exact concentration
Molecular and Pharmacological Data
| Molecular weight | 4493 |
| Sequence | Members only |
LL-37 is the only endogenous human cathelicidin antimicrobial peptide, functioning as a direct-acting antimicrobial agent and immune modulator. It disrupts bacterial and fungal cell membranes through electrostatic and hydrophobic interactions, while also activating innate immune receptors (particularly formyl peptide receptor-like 1, FPRL1) to enhance neutrophil recruitment, promote wound healing, and regulate inflammatory responses. LL-37 bridges innate and adaptive immunity by enhancing antigen presentation and modulating cytokine production.
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Recent Research
LL-37 Inhibits EV71 Infection by Upregulating STAC via the EGFR-ERK Signaling Pathway.
Correction to "An Anionic Cathelicidin Exerts Antimelanoma Effects in Mice by Promoting Pyroptosis".
Antimicrobial Peptides and Systemic Inflammation: A Network Analysis.
Source: PubMed / NCBI. Updated daily. Articles are listed for research reference only.
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View all peptidesResearch Use Only. All content on this page is provided for informational and educational purposes related to scientific research. LL-37 is not approved for human use by the FDA or any equivalent regulatory body. This is not medical advice. Do not use any substance discussed here for therapeutic, diagnostic, or preventative purposes. Consult a qualified healthcare professional before making any health-related decisions. The Peptide Volt does not endorse the use of any research chemicals. 18+ only.