Evidence strength for the context described on this page.
PEPTIDE ATLAS / IMMUNE & GUT / LL-37
Not FDA-approvedPreclinical
LL-37
ALSO KNOWN ASCathelicidin LL-37
An endogenous antimicrobial peptide with complex immune and tumor biology—not a general infection defense.
01CATEGORYImmune & gut
02REGULATORY STATUSNot FDA-approved
03COMMON ROUTETopical in human wound trials; systemic injection is marketed but unapproved and lacks human trials
04REVIEW STANDARDProduct, indication and evidence
HOW TO USE THIS PAGE
Read the profile in the order that protects the decision.
- 01Verify what it is
Confirm the exact molecule, route, regulatory lane and actual human evidence.
- 02Read the evidence limits
Unsupported claims, contraindications and uncertainty come before any protocol.
- 03Build the monitoring plan
Define the target, baseline checks, reassessment point and stop rules with a qualified clinician.
This peptide does not have an FDA-approved product or dose for the claims described here. Research dosing and vendor protocols are not consumer prescribing guidance.
RESEARCH PASSPORT
The five facts to know first.
REVIEWED
JULY 2026
Status is product-, formulation- and indication-specific.
Public education does not establish a personal treatment plan.
Official labels, regulators, trials and indexed literature where available.
Peptide hormones, growth factors and related substances may be prohibited.
Check Global DRO ↗OVERVIEW
What LL-37 is.
A human cathelicidin involved in innate immunity, antimicrobial defense and inflammation. Endogenous biology does not make systemic supplementation safe.
HOW IT IS THOUGHT TO WORK
Interacts with microbial membranes and multiple host signaling pathways; effects can be antimicrobial, inflammatory, reparative or harmful depending on tissue and context.
EFFECTS & EVIDENCE
What the evidence supports—and what it does not.
- Important endogenous immune biology
- No established consumer treatment for infection, wounds or immune resilience
- Chronic-infection treatment
- Biofilm eradication in people
- General immune enhancement
- Safe injectable use
Evidence grade: Preclinical. For an approved drug, “high” refers only to its labeled indication—not every off-label or wellness claim.
CLINICAL CONTEXT
The decision is individual.
Research interest does not establish an approved treatment, a safe personal regimen or reliable product quality. Discuss established alternatives with a qualified clinician.
Identify the outcome, formulation and population actually studied.
Review benefits, uncertainty, contraindications and better-studied alternatives.
A treatment decision needs a responsible clinician, monitoring and a review date.
This public guide does not provide a dosing, injection or self-treatment protocol. Bring the source links and the exact product into a licensed clinical consultation.
MONITORING
What should be tracked.
- Suspected infection requires organism- and site-specific diagnosis
- No biomarker makes unapproved systemic use safe
SAFETY
Risks, red flags and reasons to avoid it.
- FDA cites insufficient safety information
- Nonclinical findings suggest possible detrimental male reproductive effects
- May be protumorigenic in some tissues
- Immunogenicity, impurities and sterility risk
- Human injection
- Active cancer
- Fertility attempts
- Replacing antibiotics or wound care
Stop and seek careGet urgent medical help for trouble breathing, facial or throat swelling, chest pain, fainting, severe persistent abdominal pain, neurologic changes, severe hypoglycemia, uncontrolled vomiting or a prolonged painful erection.
CLINICIAN VISIT CHECKLIST
Six questions worth bringing with you.
Molecule or analog, salt, concentration, route, manufacturer or compounder, lot and beyond-use date.
Name the diagnosis or target, how it will be measured and the realistic time to reassess.
Ask how it compares with FDA-approved, lower-risk or better-studied alternatives.
Label, human trial, specialty guideline or clinic convention—and whether that route and formulation match.
Baseline checks, follow-up measures, interactions, pregnancy considerations and symptoms that mean stop.
Pharmacy license, prescription, identity/potency testing, sterility controls and who handles a product complaint.
Do not improvise reconstitution or convert “units” without the exact concentration. Mixing, storage and beyond-use instructions are product-specific; confirm them with the dispensing pharmacy.
SOURCES & RESEARCH LINKS
Read the record yourself.
We prioritize official prescribing information, FDA regulatory material, registered trials and indexed biomedical literature. A source supports the specific statement beside it—not every claim made about the molecule.
PRODUCTS & TREATMENT ACCESS
There is no product we can responsibly recommend.
Research-chemical and some compounded marketing; not FDA-approved.
Antimicrobial activity in a laboratory does not mean a peptide safely reaches an infection—or improves outcomes—in a person.
Evidence before affiliate revenue.
We do not rank or sell unapproved research peptides. Use the Atlas to discuss safer, evidence-backed alternatives with a qualified clinician.
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