are cats allergic to onions

Onions, garlic, chives, and leeks are in the Allium family, and are poisonous to both dogs and cats if the dose is right (if they eat a single large serving or repeatedly nibble on small amounts over time). Garlic is considered to be about five times as toxic as onions for cats and dogs.

How Much Onion Is Toxic to Cats?

Onion poisoning in cats is caused by a toxic compound in the Allium plant called N-propyl disulfide. Although any amount of onion ingestion can cause stomach upset, the most severe signs occur when more than 5 grams of onions per kilogram of their body weight, or 0.5% of their body weight in kilograms, is ingested. This is the toxic dose—however, onion toxicity has been reported in cats after ingestion of less than 1 teaspoon of cooked onions.

It’s crucial to remember that onion powder has far more power than actual onions. Consequently, cats may become poisoned by even small amounts of onion powder.

To put things in perspective, one medium onion weighs roughly ½ pound (226 grams), or one tablespoon of onion powder.

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Treating Onion Poisoning in Cats

Cats who suffer from onion poisoning frequently need to stay in the hospital until the entire extent of the damage to their red blood cells has been determined and addressed.

In addition to giving activated charcoal and other decontamination therapies to help reduce the amount of toxin absorbed into the bloodstream, your veterinarian may induce vomiting if the pet consumed onions recently—within the last two hours—in order to get rid of any leftover onion in the stomach. Unless specifically instructed to do so by a veterinarian, never induce vomiting in your cat at home as it can often cause more harm than good.

To assess your cat’s red blood cell count and determine whether they require a blood transfusion, your veterinarian will draw blood samples on a regular basis. Additional laboratory tests, such as complete blood counts and urine samples, will be conducted to evaluate other organs, such as the kidneys and liver, for any harmful alterations.

In order to help with the gastrointestinal symptoms and/or liver condition your cat may have developed, they will remain hospitalized and receive IV fluids and other medications. It’s possible that your cat requires extra oxygen to compensate for the oxygen lost from the damaged red blood cells.

Your cat’s red blood cell counts will probably need to be checked for a few weeks after recovering from onion toxicity. For a cat with onion toxicity who received prompt decontamination and medical attention, the prognosis is rather favorable. Cats with severe anemia and liver failure, as well as those who do not receive prompt, aggressive treatment, are more susceptible to it.

A pungent poisoning: Onion toxicosis in a cat. DVM 360. Accessed May 2, 2023. https://www. dvm360. com/view/pungent-poisoning-onion-toxicosis-cat.

Featured : iStock/portostock

A pungent poisoning: Onion toxicosis in a cat. DVM 360. Accessed May 2, 2023. https://www. dvm360. com/view/pungent-poisoning-onion-toxicosis-cat.

Featured : iStock/portostock

Originally from Fort Worth, Barri Morrison presently resides there. Lauderdale, Florida. She went to University of Florida for her.


How much onion is toxic to cat?

The approximate toxic dose of onions for cats is 5 grams per kilogram of body weight. However, even a teaspoon or less of onion can cause toxicity in cats. This is merely an estimate, and individual sensitivities can vary. Some cats might be affected by smaller amounts.

Why are cats allergic to onions?

Onions contain compounds called disulfides and thiosulphates which can be toxic cats and dogs if ingested. The ingestion of onions causes conditions called hemolytic anemia, Heinz body anemia, and methemoglobinemia which are all manifestation of damage to red blood cells.

Are cats affected by cutting onions?

Unfortunately, onions can do more than make your cat’s eyes water. Known as “onion poisoning,” if ingested onions can affect a feline’s red blood cells, breaking them down and causing anemia. Although the odd nibble shouldn’t cause any harm, it’s best to try and keep your cat away from the vengeful vegetable.

Do cats dislike onions?

Some of the most common smells cats hate include citrus, vinegar, peppermint, pine, onions, or spicy food. The dislike for certain smells might be rooted in survival, says Dr. Rebecca Greenstein, Veterinary Medical Advisor for Rover and Chief Veterinarian at Kleinburg Veterinary Hospital.