The Hervey Foundation for Cats
Can Cats Eat Garlic or Onions?

Can Cats Eat Garlic or Onions?

The answer is always no! It’s not about how much, or if they were cooked or not, the answer is always no. Cats cannot handle garlic or onions at all, which happen to both be members of the Allium family of vegetables. In fact, all allium vegetables are dangerous to cats, causing reactions that range in severity from serious illness to death. 


What makes garlic so dangerous to cats? It contains compounds known as disulphides and thiosulphates. These compounds will cause a cat’s red blood cells to grow so fragile they can burst, also known as hemolytic anemia. The result is not pretty, with the power to end a cat’s life. Even a small amount of garlic can cause serious harm. For example, 1/8 of a teaspoon can lead to organ damage and failure, and in some cases, death. 

Symptoms of garlic poisoning can sometimes take between two and four days to show up. When symptoms do arrive, some pet owners might already be too late to save them. This highlights the importance of keeping garlic away from your cat. If you do see them get into garlic, seek treatment immediately. Inducing vomiting can save their lives.


Less toxic than garlic, onions are still a major threat to cats. Onions also contain disulphides and thiosulphates, the same harmful compounds found in all allium vegetables. 

When a cat ingests onions, you need to immediately seek professional treatment. A veterinarian can help induce vomiting and start bloodwork to catch the extent of the poisoning. Since the compounds found in onions are similar to garlic, the symptoms will present similarly. 


If your cat shows any of the following symptoms, and there was a possibility of them getting into garlic or onions in the last one or two days, call your vet immediately:

  • Vomiting
  • Diarrhea
  • Pale gums
  • Quickened heart rate
  • Difficulty breathing
  • Fatigue
  • Collapse

Allium Family of Vegetables

As mentioned earlier, both garlic and onions are part of the allium family of vegetables. These are all similar in design and pose similar threats to cats. Some additional members of the allium family include:

  • Leeks
  • Shallots
  • Chives
  • Scallions

Get to the Vet

Any pet who has ingested garlic, onions, or another member of the allium family of vegetables needs immediate medical treatment. Do not try to treat them at home as the results are very serious and can be fatal. 

Dan Huen & Choice OMG

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