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Can Cats Eat Onions? Everything You Need to Know!

Any cat owner knows that our felines don’t always make the best choices about what they put in their mouth. Even the pickiest eaters will delight in snacking on your houseplants. So, if your kitty decides to eat either an onion plain—or a dish that has onions in it—you may ask yourself, “Can cats eat onions?” The answer is simple: no, never.

Your cats should stay away from onions at all costs, and that includes raw, cooked, and powder forms of this potent veggie. But what makes onion so dangerous for your kitty? Let’s explain.

cat face divider 2How Dangerous are Onions for Cats?

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Credit: mattycoulton, Pixabay

Onions have the component oxidant n-propyl disulfide in them. Even eating the smallest amount of onion requires veterinary attention. Onions can make your cat extremely sick, and even prove fatal if they aren’t treated immediately.

Your cat can suffer from onion toxicity because these plants cause hemolytic anemia, hematuria, or Heinz body anemia—all of which break down the red blood cells in your cat’s body. Essentially, these are types of anemia that can be extremely detrimental to all domestic pets—especially dogs and cats.

Unlike humans, their bodies just aren’t made with the correct elements to digest onions. Cats are even more sensitive than dogs to the effects of onions because their hemoglobin is very different.

Can Cats Eat Garlic, Chives, or Leeks?

Garlic, onion, leeks, shallots, and chives are in the allium family. All allium plants contain the same harmful components that onions do, with garlic being at the top of the scale. Potency does play a factor, but any exposure to allium plants is unsafe.

Because symptoms might not display for up to five days after consumptions, it’s crucial to know what to look for.3 cat face divider

Symptoms of Onion Toxicity

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Credit: OlgaBartashevich, Shutterstock

If your cat has eaten part of an onion or eaten any food containing onion, you need to get them to your vet immediately. However, if you’re unaware it happened but notice the following symptoms, know that medical attention is imminent.

Signs of onion toxicity are:
  • Lethargy
  • Weakness
  • Salivation
  • Pale gums
  • Vomiting
  • Diarrhea
  • Lack of coordination
  • Decreased appetite

If you notice any of these symptoms, don’t wait. Something may be seriously wrong with your kitty and they need you to be proactive.

Diagnosis and Treatment

When you take your cat to see their vet after eating onions, they will do an immediate evaluation of the situation with all the necessary tests. Depending on the severity or amount, your vet may push fluids, administer charcoal treatments, or do blood testing.

Recovery for onion consumption is very high, especially if you act fast and they receive speedy medical attention. Even trace amounts of onion can damage your cat’s red blood cells, so observation and treatment are time-sensitive and crucial.yarn ball divider

Foods to Watch Out For

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Credit: mattycoulton, Pixabay

Some foods might contain onion without you realizing it. Also, rarely, some products that are designed for cats could contain this lethal ingredient. Be very careful and always review any new food or snacks. If you find your cat reacting badly to a recently bought snack, it may be time to check the label.

You might not realize it, but many things contain onion powder, which is still highly toxic for cats. You might think nothing of sliding your cat a nice sliver of delicious chicken from takeout—but beware of the seasonings. Onion is remarkably popular for food flavoring.

Some food that may contain onion include:
  • Baby food
  • Seasoned meat
  • Certain types of broth
  • Gravy
  • Several sauces
  • Canned soup

Before you offer any table scraps or human food to your cat, do a quick sweep of what additives are in the recipe.cat + line divider

Cats and Onions: Final Thoughts

Keep your cat away from onion in all forms at any cost. It doesn’t matter if a portion of food only has a tiny amount of onion—it’s bad news for your feline. Plus, you’ll rack up a ton of vet bills that you can avoid simply by keeping them away in the first place.

Of course, we all know that cats are sneaky and do what they wish. If your innocent, defenseless feline swiped a piece of onion from your plate, contact your vet for further advice.


Featured image credit: mattycoulton, Pixabay