Leeks are among the more potent members of the onion family, and they are usually eaten in volume rather than as a garnish. Cooking offers no protection, and signs of anemia can be delayed by several days.
Call a vet or poison control now. Do not wait for symptoms.
ASPCA Animal Poison Control (888) 426-4435 or Pet Poison Helpline (855) 764-7661. A consultation fee may apply.
Educational reference. Not individualized veterinary advice.(more)
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Part of our guide to Hidden Onion and Garlic in Everyday Dog Food Risks.
Read the general guidance and keep your dog's exposure details ready for a veterinary call. This checker cannot decide whether an exposure is safe.
Why Leeks is dangerous
Leeks are among the more potent members of the onion family, and they are usually eaten in volume: a leek in a soup or a gratin is a lot of allium by weight, not a garnish. Same mechanism, oxidative damage to red blood cells leading to anemia, with cooking offering no protection. The onset is delayed, so clinical signs may not appear for several days.
Part of the Onion guide
For related dog-safety questions and product-by-product answers, see the complete onion guide.
Signs to watch for
Weakness, pale gums, dark urine, lethargy, panting, collapse in severe cases, vomiting, reduced appetite
Related items
Check the exact item or ingredient before assuming two similar exposures carry the same risk.
What to do next
Work out roughly how much was eaten and in what dish, then call your vet, and plan to watch your dog for several days, not just tonight.
🚨Step-by-step: what to do in the first 10 minutes →Available 24/7. A consultation fee may apply.
Volume is what makes leeks worse
Most allium accidents involve a trace. Leeks are the exception, because they are treated as a vegetable.
1. A soup portion is a real dose
Where onion usually reaches a dog as seasoning, leeks reach it as bulk. A serving of leek and potato soup or a gratin can represent a substantial fraction of a small dog's reported toxic threshold in one go, and neither simmering nor roasting reduces the organosulfur compounds responsible. Allium potency by form, and the reported dose figures →
FAQ
Toxic by weight; reported problem doses for onion sit around 15 g/kg and leeks are in the same potent bracket. Because they are eaten in quantity, a bowl of leek soup is a more serious exposure than most people expect.
No, not for a real portion. Anemia develops out of sight over days and needs bloodwork to catch.
Any real amount, any small dog, a Japanese breed, or any weakness, pale gums, or dark urine at any point in the week after.
- ASPCA Animal Poison Control Center, people foods to avoid feeding your pets (onions, garlic, chives)
- Pet Poison Helpline, onion and garlic toxicity
- Merck Veterinary Manual, Allium species toxicosis
- Merck Veterinary Manual: garlic and onion (Allium spp) toxicosis in animals
- Pet Poison Helpline: garlic
- Pet Poison Helpline: onion
- ASPCA Animal Poison Control: people foods to avoid feeding your pets
- Merck Veterinary Manual: food hazards