LL-37

LL-37 is a cathelicidin-derived peptide that owners most often ask about in relation to immune balance and skin defence.

LL-37 is a 37-amino-acid peptide derived from the cathelicidin precursor hCAP-18. It plays a part in the body's innate immune defences and in the biology of skin and mucosal surfaces. When owners raise LL-37 with our veterinary team, it is usually in the context of an animal that seems to pick things up easily, or one with a stubborn surface irritation. Interest is generally in supporting the animal's own defences rather than in treating an infection. Suspected infection is a veterinary matter and needs to be examined, diagnosed, and treated appropriately — a peptide is not a substitute for that, and delaying proper treatment can make an animal worse. Our supervising veterinarian will say plainly when LL-37 is not the right conversation. LL-37 is not approved by the FDA for use in animals.

04What Owners Ask About

What owners ask our veterinary team about LL-37

Owners in our program commonly bring up LL-37 in connection with:

General wellness support
Owner questions we hear often
Species-specific considerations
How our veterinary team evaluates fit

“This is a commonly discussed compound in conversations with our veterinary team. Below are the areas owners most often ask about.”

General information only, shared to help you prepare for a conversation with our veterinary team. It is not a treatment plan, dosing, or a guarantee of any outcome — your animal's plan is set by our supervising veterinarian.

§Dosage Chart

LL-37 — your animal dosing reference

Awaiting veterinary sign-off. These figures are finalised by our supervising veterinarian for your individual animal. Nothing here should be acted on until your veterinary team has reviewed your pet's species, weight, age, and health history.

LL-37 dosing reference for your animal, populated and approved by the supervising veterinarian.
Weight / stage	Amount	Frequency	Duration	Vet notes
Small animal	[VET-APPROVED VALUE]	[VET-APPROVED VALUE]	[VET-APPROVED VALUE]	[VET-APPROVED VALUE]
Medium animal	[VET-APPROVED VALUE]	[VET-APPROVED VALUE]	[VET-APPROVED VALUE]	[VET-APPROVED VALUE]
Large animal	[VET-APPROVED VALUE]	[VET-APPROVED VALUE]	[VET-APPROVED VALUE]	[VET-APPROVED VALUE]

Every protocol in our pet peptide program is set under the guidance of our supervising veterinarian. Contact our veterinary team to have a plan reviewed for your animal.

Vet-supervised program

LL-37 is offered through our vet-supervised pet and animal peptide program. Every plan — including whether LL-37 is appropriate for your animal — is set by our supervising veterinarian after reviewing your animal's history. Browse our program →

Veterinarian-Supervised Program

Every peptide protocol in this section is set and overseen by our supervising veterinarian. Nothing on these pages is a diagnosis, a prescription, or a substitute for examining your animal — dosing is determined individually after veterinary review of your pet's species, weight, age, medications and health history. Peptides are used alongside, never instead of, care from a licensed veterinarian. These products are not approved by the FDA for use in animals. If your animal is unwell, injured, or showing new symptoms, contact a veterinarian first.