Toxic to dogs · Foods

Are Leeks toxic to dogs?

High severity No safe amount — No amount is considered safe.

Yes, Leeks are highly toxic to dogs. Exposure can cause serious illness and needs prompt veterinary attention. No amount is considered safe.

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Are leeks toxic to dogs and cats?

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What to do right now

  1. Take away any leeks or leftovers your dog hasn't eaten, and check the counter, the bin and the vegetable patch so it can't eat more.
  2. Call your vet or an animal poison line now, even if your dog seems fine. In the US: Pet Poison Helpline (855) 764-7661 or ASPCA Animal Poison Control (888) 426-4435 (both may charge a fee).
  3. Don't make your dog vomit and don't give it anything by mouth unless a vet tells you to.
  4. Tell the vet what your dog ate (raw or cooked leeks, a soup, leftovers or a dried mix), roughly how much and when, and your dog's weight, age and breed. Keep the packaging or the recipe: onion, garlic or chives in the same food matter too.
  5. Tell the vet about any medicines your dog takes. The 2005 toxicology brief says some medicines, such as acetaminophen (paracetamol), are likely to make a pet more susceptible to Allium poisoning.

Go to an emergency vet if

  • Your dog is weak, tires quickly on walks or collapses. The Merck Veterinary Manual lists weakness, exercise intolerance and collapse among the signs of Allium poisoning.
  • Your dog's gums look pale, or its gums or skin look yellow (jaundice).
  • Your dog's urine is red, brown or dark. This can mean red blood cells are breaking down.
  • Your dog breathes fast or pants, or its heart races.
  • Your dog is unconscious, has trouble breathing or has a seizure. Take it straight to a vet clinic.
  • Your dog ate a large amount or a concentrated form, such as a dried soup mix or a powder, or it is a Japanese breed such as an Akita or Shiba Inu, even if it shows no signs yet. Signs often appear only after several days.

Symptoms to watch for

  • nausea
  • drooling
  • abdominal pain
  • vomiting
  • diarrhea
  • lethargy
  • pale gums
  • increased heart rate
  • increased respiratory rate
  • weakness
  • exercise intolerance
  • collapse
  • anemia

How much is dangerous

No toxic dose of leeks has been published for dogs. The only dose figures in the sources we checked are for onions, and none of them says how leeks compare. Pet Poison Helpline says leeks are poisonous to dogs, that Japanese breeds such as the Akita and Shiba Inu are more sensitive to Allium plants, and that the amount eaten and the size of the animal both affect what is toxic to a given pet. A 2005 toxicology brief in Veterinary Medicine says Allium poisoning typically follows a single large amount or repeated small amounts, and that cooking doesn't reduce the risk. Your vet judges the risk from what your dog ate, roughly how much, and its size and breed.

When signs appear

Signs are usually delayed. The Merck Veterinary Manual says damage to red blood cells begins within 24 hours and peaks in about 72 hours, and that the red blood cells typically break down (hemolysis) 3 to 5 days after exposure. Signs are generally not noticed until then, usually a few days after your dog ate the leeks. The 2005 toxicology brief says signs may appear within one day if a large amount was eaten, but more often develop after a lag of several days. Early signs can include vomiting, diarrhea, belly pain, loss of appetite and dullness, and soon after eating, breath that smells of onion or garlic. As anemia develops, your dog may have pale gums, weakness, fast breathing or panting, a racing heart, yellowing (jaundice) and red or brown urine. None of the sources we checked says how long signs last. The ASPCA warns that many poisons have a delayed effect, so call your vet even if your dog seems fine.

Why it's dangerous

Leeks cause oxidative damage to red blood cells, leading to hemolysis (rupture) and subsequent anemia, while also causing gastrointestinal irritation.

Toxic compound: disulfides, thiosulfates

How vets treat it

There is no specific antidote for Allium poisoning. If your dog ate the leeks recently, the vet may make it vomit: the 2005 toxicology brief says this can help a dog with no signs yet, if there are no complicating factors and it ate within the last one or two hours. Activated charcoal may follow, although the Merck Veterinary Manual says it is unknown whether it binds the sulfur compounds from Allium plants. Blood tests confirm the diagnosis by finding Heinz bodies (clumps of damaged hemoglobin inside red blood cells) and anemia. The vet rechecks the blood over several days, because that is when the anemia is usually at its worst. A dog with life-threatening anemia may need oxygen and a blood transfusion, and a drip (IV fluids) helps protect the kidneys from the hemoglobin released by broken red blood cells.

Outlook

No recovery times or survival figures for leeks were found. The 2005 toxicology brief says the outlook depends on the plant involved, how severe the anemia is and whether supportive care is started, and the Merck Veterinary Manual lists collapse and death among the possible outcomes of Allium poisoning. A 2016 review reports 69 dogs poisoned by Allium plants that were recorded by the Veterinary Poisons Information Service between 1994 and 2008. Vomiting, diarrhea and belly pain were reported, and less often anemia, blood in the urine and seizures. Two dogs died and two were put to sleep.

Where pets are exposed

  • Vegetable gardens. The leek is a hardy, cool-season vegetable, and Utah State University Extension says that in most areas it can be kept in the garden over winter, with soil heaped around the plants and a thick layer of mulch, leaves or soil on top.
  • Kitchens. Leeks go into soups, salads and casseroles, and can be frozen, pickled, canned or dried at home. Cooking doesn't make them safe: a 2005 toxicology brief in Veterinary Medicine says cooking or spoilage does not reduce the potential toxicity of Allium plants, and a 2016 review says cooking, drying and processing don't remove it.
  • Leftovers and ready-made foods. The 2005 toxicology brief lists juice, powdered cooking preparations, dried plant material and any food made from or containing an Allium plant as potentially toxic to dogs and cats. The Merck Veterinary Manual says poisoning in dogs and cats is most often linked to concentrated forms, such as dried flakes, powders and dry onion soup mixes.
  • The Allium family. Leeks belong to the same group of plants (the genus Allium) as onions, garlic, chives, shallots and scallions, and the 2005 toxicology brief says all Allium species and the products made from them can be toxic to dogs and cats. Pet Poison Helpline says leeks, onion, garlic and chives are all poisonous to dogs, cats and livestock. The ASPCA lists the leek (Allium ampeloprasum) as toxic to dogs, cats and horses.
  • The toxins are sulfur compounds. The Merck Veterinary Manual says chopping, cooking and chewing release them from the plant, and so does the action of bacteria in the gut. The ASPCA names n-propyl disulfide as the toxic principle in leeks.

Prevention

  • Don't share leeks, raw or cooked, or dishes made with them, such as soups and casseroles, with your dog or cat. The 2005 toxicology brief says cooking doesn't reduce the potential toxicity of Allium plants.
  • Don't give leftovers that contain leeks, onion or garlic as a regular treat. The 2005 toxicology brief says poisoning can follow repeated small amounts as well as a single large one.
  • Check the label before you share any food made for people, such as broth, a soup mix or baby food. The 2005 toxicology brief lists powdered cooking preparations and dried plant material among the potentially toxic forms, and the authors of a 1998 study advise against feeding cats baby food that contains onion powder.
  • Put leek trimmings straight into a bin your pet can't open, and keep your dog out of the vegetable patch. Leeks can stay in the garden all winter.
  • Keep onions, garlic, chives and shallots out of reach too. The 2005 toxicology brief says all Allium species can be toxic to dogs and cats, and Pet Poison Helpline says onion, garlic, chives and leeks are all poisonous to them.

Good to know

Signs of poisoning can be delayed for several days. Cats and Japanese dog breeds like Akita and Shiba Inu are more sensitive.

Common questions

Are leeks toxic to dogs?

Yes. The ASPCA lists leeks as toxic to dogs, with vomiting, breakdown of red blood cells (hemolytic anemia), blood in the urine, weakness, a high heart rate and panting as signs. Pet Poison Helpline says leeks, like onion, garlic and chives, are poisonous to dogs, and that Japanese breeds such as the Akita and Shiba Inu are more sensitive. Signs of anemia usually take a few days to appear, so call your vet or a pet poison line if your dog ate leeks, even if it seems fine.

Are leeks toxic to cats?

Yes. The ASPCA lists leeks as toxic to cats, and the Merck Veterinary Manual says cats are the species most sensitive to Allium poisoning. A 2005 toxicology brief in Veterinary Medicine says normal cat hemoglobin is about two to three times more susceptible to oxidative damage than that of other species. No toxic dose of leeks has been published for cats, so call your vet or a pet poison line if your cat ate any leek, raw or cooked.

Are cooked leeks or leek soup safe for dogs and cats?

No. A 2005 toxicology brief in Veterinary Medicine says cooking or spoilage doesn't reduce the potential toxicity of Allium plants, and a 2016 review says cooking, drying and processing don't remove it. The 2005 toxicology brief also lists juice, powdered cooking preparations, dried plant material and foods containing an Allium plant as potentially toxic to dogs and cats. The sources we checked don't separate the white stem from the green leaves. Call your vet if your pet ate leeks in any form.

Why are leeks dangerous for pets?

Leeks contain sulfur compounds, released when the plant is chopped, cooked or chewed and by bacteria in the gut. Once absorbed, they damage red blood cells: damaged hemoglobin clumps into Heinz bodies, the cells become fragile and break down, and the pet becomes anemic (hemolytic anemia). The Merck Veterinary Manual says this damage begins within 24 hours, but the cells typically break down 3 to 5 days after exposure, which is why signs are delayed. The hemoglobin released into the urine may also damage the kidneys.

Are leeks as dangerous as onions or garlic?

None of the sources we checked compares them. The Merck Veterinary Manual includes leeks among the Allium plants but says garlic and onions are the ones most often linked to poisoning. A 2005 toxicology brief in Veterinary Medicine lists leeks with onions, garlic and chives as commonly involved in poisoning of dogs and cats, and Pet Poison Helpline says all four are poisonous to them. No toxic dose has been published for leeks, so call your vet whatever amount your pet ate.

My dog or cat ate leeks. What should I do?

Take away any leftovers and call your vet or a pet poison line now, even if your pet seems fine. In the US: Pet Poison Helpline (855) 764-7661 or ASPCA Animal Poison Control (888) 426-4435 (both may charge a fee). Don't make your pet vomit or give anything by mouth unless a vet tells you to. Note what it ate, roughly how much and when. Signs of anemia usually take a few days to appear, so over the following days watch for weakness, pale gums, fast breathing and red or brown urine.

Sources

This page is informational and is not veterinary advice. If your pet has been exposed to something risky, contact your vet or an animal poison control line right away.

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