Red: toxic
No, dogs must not eat leeks, even cooked. Like onions, garlic and chives, leeks belong to the allium family and can damage red blood cells.
Why leeks are dangerous
The ASPCA lists leeks as toxic to dogs, cats and horses in its plant database. It identifies N-propyl disulfide as the toxic substance. According to the MSD Veterinary Manual, sulphur-containing compounds damage red blood cells, whether the alliums are raw, cooked or dried. Anaemia often appears only after several days, typically 3 to 5 days after ingestion according to MSD. The Pet Poison Helpline says Japanese breeds such as Akitas and Shiba Inus are more sensitive.
What are the signs?
The ASPCA lists vomiting, destruction of red blood cells, blood in the urine, weakness, a rapid heartbeat and panting. MSD also lists pale or yellowish mucous membranes and collapse.
What to watch for
- Leeks are often hidden in soups, stews, quiches, sauces and stock.
- According to MSD, vegetable stock powders and dried mixes are particularly concentrated.
- Do not put kitchen leftovers in your dog’s bowl, and dispose of vegetable scraps securely.
What if your dog has eaten leeks?
Call your vet or an emergency veterinary service immediately, even if your dog still seems well, because signs are often delayed. Be ready to explain what was eaten, roughly how much, when it happened and how much your dog weighs. Do not induce vomiting yourself or give home remedies.
If you suspect poisoning, take your dog to a vet or an emergency veterinary service immediately.
Snacks count towards the daily food allowance. Our free food calculator works out how much your dog needs, and you can find a complete feeding plan with guidelines for treats in our book “Hundeernährung und Futterplan” (book in German). New to life with a puppy? Our free Puppy Starter Pack can help. And if you would love to see your dog on your living room wall, explore our dog portraits from your own photo, available as a framed portrait or digital file.
Further reading
- Christmas with your dog: what to arrange beforehand
- Calculating your dog’s food allowance: how much your dog really needs
- Puppy checklist: essentials and the first 3 days
Sources, accessed on 20.10.2026: ASPCA Animal Poison Control, Toxic and Non-Toxic Plants: Leek (Allium ampeloprasum), Toxic to Dogs; MSD Veterinary Manual, Garlic and Onion (Allium spp) Toxicosis in Animals; Pet Poison Helpline, Leeks.
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