Pets and Onions – What are the Top Dangers?

Pets and Onions - Healthier Pets Today

Onions can harm your pet in ways other than just bad breath. This solid culinary favorite might flavor your food but contains toxins that can seriously harm pets. It’s good to learn about pets and onions, as you may be surprised about the damage this home staple can cause to your pet.

Each Layer Can Poison Pets

Pets and Onions - Healthier Pets Today

Pets and onions have been controversial among many pet owners and veterinarians. Many people adore onions, and we consume them in many delicious foods. We must remember that what is tasty and fabulous for us may harm our pets.

Disulfides and thiosulphates in onions can be toxic to cats and pets. Damaged red blood cells from eating onions can cause; 

  • Heinz body anemia
  • Methemoglobinemia 
  • Hemolytic anemia

The red blood cells in your pet’s body can become extremely fragile and burst due to the compounds in onions.

Early-onset vomiting, diarrhea, and anemia-related symptoms like fatigue, breathlessness, pale, yellow, or “muddy”-colored gums, rapid breathing, and an elevated heart rate are all signs of this condition. While the symptoms of anemia may not show up for several days up to a week after your pet eats onions, vomiting and diarrhea frequently do. Additionally, your pet could experience stomach pain and turbid urine.

Are All Types Of Onions Harmful To Pets?

Pets and Onions - Healthier Pets Today

All onions are harmful to your pet, whether cooked, raw, or even free-dried. Just a few onions can poison your cat or pet, and cats are more vulnerable than pets to the effects of onion poisoning. For example, Akita, Shiba Inu, and Japanese Chin pets may be genetically more prone to the condition than other pet breeds.

Even a tiny amount of onion consumption—5 g/kg for cats and 15 to 30 g/kg for pets—has been linked to clinically significant red blood cell damage. Animals that consume more than 0.5% of their body weight in onions at once frequently develop onion toxicosis.

Regarding pets and onions, it’s crucial to be aware that their weight, breed, and past medical history can affect how toxic an onion they consume. Call your veterinarian immediately or the Pet Poison Helpline at 855-289-0358 if you think your pet may have eaten an onion. 

How Bad Are Onions For pets?

Pets and Onions - Healthier Pets Today

Onions can be toxic depending on how much your pet eats and how big it is. 100g of onions for every 20kg of a pet’s weight can have harmful effects, according to The American Kennel Club. A small pet can be fatally affected by just a tiny amount of onion. We advise against giving any pet any onion at all as a precaution.

Pets should avoid eating any part of an onion, including the flesh, leaves, juices, and powders made from this vegetable. Therefore, keeping your garden’s onions fenced off and away from opportunistic pets is an excellent idea if you plan to grow onions there.

Pets and Onions: Symptoms

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If your pet ate onions, they might become ill in a day or two, but anemia symptoms can sometimes take several days to appear. The following signs could appear:

  • A Diminished Appetite
  • White Gums
  • Lethargy
  • Weakness
  • Collapse
  • Urine With A Red Tint
  • Diarrhea And/Or Vomiting
  • Higher Heart Rate
  • Panting

Take your pet to the veterinarian as soon as you see any of the symptoms mentioned above. A prompt response can significantly alter the situation. So, that your pet can be diagnosed and treated.

What About Onion-Flavored Broth?

Regarding the risk of pets and onions, it is best to avoid giving your pet any food cooked with onions. Although a tiny amount of onion is unlikely to cause issues, Hinder advises that it is safer to avoid it entirely.

This includes using onions in your broth if you cook for your pet or some snacks off your plate. Similarly, when buying a pre-made broth, read the labels and choose one without onions.

Hinder pet guardians to watch for the ingredient onion powder in prepared foods and to avoid using it in any recipes they will be feeding their pets because it is made of dried and ground onions and may be harmful to them.

All parts of the onion, including the juice, flesh, and even the leaves, are problematic for pets. Never prepare anything that contains onions, not even onion powder, for your pet.

Particular Foods to Consider

Pets and Onions - Healthier Pets Today

Many foods we eat contain onions, including foods you might not think can pose a threat to your pet. Before you think about allowing your pet to indulge in these foods, make sure they don’t contain any onions:

Chinese food, tomato sauce, and pizza

certain baby foods

According to Dr. Tina Swan, a veterinarian who works for Nationwide Pet Insurance, the toxicity of pets and onions can be hazardous and expensive to treat.

When pets eat table scraps, it can be challenging to pinpoint what exactly makes them toxic. Swan, a specialist in animal emergency care, remembers identifying a patient with symptoms of food toxicity. She recalls a young pet who showed partial paralysis and weakness in his back legs. “The owner had fed the pet some macadamia-crusted salmon with sauteed onions the night before, which provided the problem’s first hint.

What’s the best way to prevent accidentally giving your pet poison? Swan always advises clients against giving table scraps to their pets. In addition to onion powder, which is present in many foods in varying amounts, many sources of onion (cooked or raw) can potentially be toxic to pets. Although it does take a certain amount to be a problem, it can be challenging to determine this when dealing with table scraps.

How to Handle a Poisoned Pet

Pets and Onions - Healthier Pets Today

Call your veterinarian immediately if your pet may have eaten an onion of any kind. Although the condition is treatable, it’s crucial to see a vet as soon as possible to avoid harming your pet’s red blood cells. If your veterinarian is unavailable, always have the phone number and address of a nearby emergency veterinary clinic on hand.

If the condition is severe, a lengthy hospital stay and, in rare circumstances, a blood transfusion may be required.

Pet Poison Helpline charges a per-case fee. PPH and Nationwide Pet Insurance are not partners.

How Is Onion Toxicity Treated In Pets?

The course of treatment for the toxicity of pets and onions depends on how much your pet consumes. You can get them to the doctor quickly enough. The veterinarian may be able to induce vomiting to remove the onion from your pet’s system before it can be digested if you find out your pet has eaten an onion. This only functions as a preventative measure if you can act quickly enough.

Your pet will require supportive care if they exhibit onion toxicity symptoms. A blood transfusion might be necessary for dire situations where the pet’s condition is critical. If your pet’s red blood cells are seriously compromised, your veterinarian will offer ongoing care to help them return to their typical, joyful selves.


Because they are bulbs, like garlic, and do not grow as deeply as other root vegetables, onions are distinct from the other members of the family of root vegetables. Along with chives and leeks, onions are available in white, yellow, and red bulbs. Both cooked and raw, they add flavor to a variety of dishes. Onion toxicity symptoms are anemia symptoms, which appear when your dog’s red blood cell count is low. Be looking for pale gums, weakness, decreased appetite, and lethargy. Clinical symptoms of animal poisoning, according to the ASPCA’s animal poison control website (, include vomiting, panting, and an elevated heart rate. Take your dog to their vet immediately if you notice these signs.