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LL-37: what needs checking?

LL-37
LL-37 is the name of a peptide in FDA’s records about medicines made to order.

FDA (Food and Drug Administration) reviews medicines for US approval.

What does the FDA record say?

People or groups asked FDA to consider allowing LL-37 as an ingredient for medicines made to order, then took their request back. The FDA page is marked current April 22, 2026.

FDA still lists safety concerns for LL-37.

Does “withdrawn” mean it has been cleared?

No. Taking back the request did not give approval or permission for a pharmacy to use LL-37. It did not put LL-37 under FDA’s temporary policy for certain ingredients awaiting a decision.

In the record checked here, LL-37 is not on the list covered by that policy.

While FDA considers whether to allow certain ingredients, its policy describes a plan to hold off on action against pharmacies using them. Pharmacies must meet the policy’s conditions. This is not approval or a statement that using an ingredient is lawful.

For LL-37, get the pharmacy’s explanation of which rule permits its use. Taking back the request does not answer that question.

That distinction reflects the record checked on September 26, 2026.

What can this guide say about immune benefits?

The sources cited here do not establish that LL-37 helps the body fight illness. Ask what benefit is being offered and which study in people supports it.

Ask whether the study used LL-37 and involved people with your health problem. Ask what it found and what it could not answer.