PeptideSearch

LL-37

Animal studies only

Get notified when the evidence changes.

Almost all the research is in animals. We do not know if the same thing happens in people.

Compiled and reviewed by the PeptideSearch Editorial Team · Status checked 2026-04-15

Also called hCAP18 / Cathelicidin antimicrobial peptide

A natural germ-fighting peptide the immune system makes. Studied for infections and wound healing.

Official status: 503A Category 2 – significant safety risk · Checked 2026-04-15

Can a doctor prescribe this?

Small pharmacy (503A)
Never put forward to FDA
Large outsourcing facility (503B)
Never put forward to FDA

Still restricted. The FDA has said it plans to review this one by February 2027.

503A is a pharmacy making a single prescription for one patient. 503B is a facility making batches. They are governed by separate lists. Where a category is shown, it is a position on the FDA's list of substances that have been put forward and are still being worked through — not the final list, which is set by rulemaking. Category 1 means the FDA does not plan to act against a pharmacy that makes it while the review runs.

Lab suppliers we list: 9

Doses used in research

Taken word for word from the studies and trials listed on this page. This is not a recommendation and not a dose for anyone to take.

This is a sample, not the whole literature.

About 32,000 papers mentioning this compound have been published. We show a selected sample of 92 of them, not the full literature. How we choose them · count checked 2026-08-23

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