LL-37
Also known as Cathelicidin, CAP-18 fragment
LL-37 is the only cathelicidin antimicrobial peptide made in humans. It is produced by white blood cells and skin, kills bacteria by disrupting their membranes, and also signals to the immune system. It has been trialled as a topical treatment for leg ulcers. It is not an approved medicine.
Who has LL-37 in stock
| Supplier | Listing | Price | Per mg | |
|---|---|---|---|---|
| AminoPeptidesBest valueUK | LL-37 Peptide | 5mg | £67.00 | £13.40 | In stock, go |
| HiPeptidesUK | LL-37 | £59.99 | – | In stock, go |
| 99 Purity PeptidesUS | LL-37 Spray | US$64.99 | – | In stock, go |
| Certa PeptidesEU and UK | LL-37 | €76.99 | – | In stock, go |
Live stock is checked hourly at 10 suppliers. A further 7 vetted suppliers have no live feed yet, so we never show them as in stock. We earn a commission from some supplier links when you buy. It costs you nothing extra and never changes the order, which is by price per mg.
What it has been studied for
- Healing of venous leg ulcers, applied to the skin, in a phase 2 trial
- Bacterial biofilms in laboratory studies
- Its role in psoriasis and rosacea, where raised levels are linked to inflammation
Evidence level: Early human data. Human data exists, but read the details above before assuming it applies to you.
What happened in human trials
Tested as a cream on leg ulcers in a small trial, where it was well tolerated. Injected LL-37 is untested, and the body's own LL-37 is linked to psoriasis, lupus and rosacea flares.
Prohibited in drug-tested sport under the World Anti-Doping Code.
UK legal status
Not licensed as a medicine in the UK. Sold as a research chemical only.
Handling
Supplied as a lyophilised powder. Reconstituted with bacteriostatic water and refrigerated once mixed. Commonly 5mg per vial.
Questions
Is LL-37 an immune booster?
It is part of the immune system, but more is not simply better. Raised LL-37 is linked to inflammatory skin disease and some autoimmune conditions, so its effects depend heavily on context.
Before you buy anything, run the four-question check for red flags that apply to you.