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Immune / antimicrobial

LL-37

Also known as Cathelicidin

The body's own antimicrobial peptide, used against stubborn infections.

Emerging evidence

Overview

LL-37 is a naturally occurring antimicrobial peptide - it is produced by your own immune cells and epithelial tissues as part of the body's first line of defense. In the peptide therapy context, synthetic LL-37 is used to augment this function in people dealing with infections or immune compromise. How it works: LL-37 is an active member of the cathelicidin family of antimicrobial peptides. It disrupts bacterial cell membranes, dismantles biofilms (the protective structures bacteria form to resist antibiotics), and has activity against viruses and fungi as well. Beyond direct antimicrobial activity, it also has immune signaling roles - it helps recruit and activate immune cells at sites of infection. Who tends to use it: People with primary immune support goals, particularly those dealing with stubborn or recurrent infections where biofilm involvement may be a factor. It also carries minor secondary ratings for gut health and recovery. It is often used alongside Thymosin Alpha-1 in more intensive immune protocols. How it is taken: LL-37 is given by subcutaneous (SC) injection. Dosing and frequency are per protocol - both are set at consult because LL-37 is a specialized compound used in specific clinical situations rather than general wellness maintenance. Cycles are kept short and monitored. What to expect: LL-37 is not a general wellness compound. It is used for targeted immune support in situations where its specific antimicrobial and biofilm-disrupting properties are relevant. Safety: The record notes that LL-37 can cause injection-site reactions and is categorized as specialized use. It is classified as emerging evidence. There are no excludeIf flags. Your licensed provider in the PepDepo network will evaluate your specific immune situation and determine whether LL-37 is appropriate, and will set your protocol at consult.

At a glance

Route
SC injection
Dose
Per protocol
Frequency
Per protocol
Timing
Any time
Cycle
Short, monitored

Combining

Stacks well with: Thymosin Alpha-1

Safety

Can cause injection-site reactions; specialized use.

Regulatory: Research compound.

Questions

How is LL-37 given?

By subcutaneous (SC) injection. Both dose and frequency are per protocol - they are set at consult because this is a specialized compound.

Why is dosing per protocol rather than a published range?

LL-37 is described as specialized use. Its application depends on the specific immune situation being addressed, so dosing is individualized rather than following a one-size-fits-all range.

What are the main things it is used for?

Immune support is its primary use. Gut health and recovery are minor secondary areas. It is particularly relevant when biofilm-forming bacterial infections are involved.

Are there injection-site reactions?

Yes, the record specifically notes that injection-site reactions can occur. This is the main safety note for LL-37.

Are there any contraindications?

No excludeIf flags are listed - no contraindications for pregnancy or cancer history appear in the record. The specialized-use classification means it is used in targeted situations rather than broadly.

How long are the cycles?

Short and monitored. Duration is determined at consult based on your situation.

Does it pair with other peptides?

Thymosin Alpha-1 is the listed synergy partner. Both are immune-modulating peptides and are sometimes combined in intensive immune protocols.

Related protocols

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Exact dosing is set with a licensed provider in the PepDepo network. This page is education, not a prescription.

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Education only, not medical advice. Peptides discussed are for informational purposes and many are not FDA-approved. Eligibility, prescribing, compounding, and dispensing are handled by appropriately licensed entities. Exact protocols and dosing are set with a licensed provider in the PepDepo network at consult. Content is pending clinical review.