Suspect poisoning? US: ASPCA Poison Control (888) 426-4435 · UK: 01202 509 000 · Severe symptoms → nearest emergency vet now.

How much leek is toxic for a 4 kg cat if it's cooked into a sauce?

Cats · Food safety

Last reviewed: 2026-09-05 · Reference ranges: ASPCA, Pet Poison Helpline & Merck Veterinary Manual

Short answer

Any amount of leek is toxic for cats, and there is no safe dose. Leeks, chives, onions, and garlic all belong to the same plant family and contain compounds that damage red blood cells, leading to anemia. The risk is present whether the leek is raw, cooked, or powdered in a sauce. If your cat has ingested any leek, watch for signs like weakness, pale gums, or red-tinged urine, and contact your vet or the ASPCA poison line at 888-426-4435 right away for guidance.

Leek & chives — Food safety facts

Do not feed · Cats · full breakdown on the linked food page

Toxic, same family as onion and garlic. Causes red blood cell damage and anemia.

Dogs and cats carry the same rating (Do not feed), so the notes below hold for either pet.

Leek & chives should not be given to cats at all. Even a small amount can do harm, so there is no portion small enough to be safe.

Do not induce vomiting and do not give milk or oil to “dilute” it. Note the food and roughly how much was eaten, then call your vet or a pet poison hotline and follow their advice on whether to bring the pet in straight away.

Why these cautions matter

Garlic and onion damage a pet's red blood cells and can bring on anaemia. Signs are often delayed for several days, so looking fine straight afterwards does not rule it out.

The full verdict, portion guidance and serving notes are collected on the Leek & chives food facts page.

Open the full food page: Leek & chives food facts →