Can Dogs Eat Onions?

No, dogs shouldn’t eat onions. These vegetables contain a compound called N-propyl disulphide which is highly toxic for dogs. This compound can cause the breakdown and eventual destruction of red blood cells and lead to anaemia. In extreme cases, onion poisoning can be fatal for dogs.

All parts of the onion plant are toxic to dogs, including the flesh, leaves, juice, and processed powders. Whether raw or cooked, fried or powdered, onions and the rest of the allium family (garlic, shallots, leeks, and chives) are harmful to dogs.

Are Onions Bad for Dogs?

Yes, onions are toxic to dogs and should not be eaten. Whether cooked or raw, all parts of the onion and onion plant are toxic to dogs, including the bulb, leaves, juice, and processed powders.

No form of onion should be included in your pet’s diet or treats. Care should also be taken to prevent dogs from getting into any gardens with onions or wild onion patches.

Onions belong to the genus Allium, and their scientific name is Allium cepa (cepa is Latin for “onion”). 

They contain a toxic compound, N-propyl disulfide, that damages red blood cells, which leads to their breakdown and destruction.

This process, called hemolysis, results in anemia and red or brown discoloration of urine. With anemia, the body’s organs are no longer getting enough oxygen. In severe cases, this can result in organ failure and death.

Can Dogs Eat Onions

How Much Onion Can Make a Dog Sick?

Another reason that onions and other alliums are dangerous is that it doesn’t take a lot to cause serious health problems in dogs. Generally speaking, toxicity occurs when a dog ingests more than 0.5% of their body weight in onions at one time.

To put it simply, even a small amount of onion, garlic, or other toxic allium food can poison a dog easily. The smaller the dog, the greater the danger eating a small bit of onion might not harm a 150-pound mastiff, but it can cause serious health symptoms in a 10-pound chihuahua.

You should always be mindful of where you store your onions and make sure to keep them away from your dog.

What should I do if my dog eats onion?

If your pup ate any kind of onion, it is extremely important that you consult your veterinarian, an emergency clinic or the Pet Poison Helpline immediately. Symptoms occur as a result of onion poisoning can take a while to appear, generally after 3-5 days from digestion, and include:

  • Lethargy
  • Panting
  • Diarrhea
  • Vomiting
  • Weakness
  • Fainting
  • Discolored urine

Treatment normally involves the inducement of vomiting, flushing out the tummy, and using activated charcoal to prevent toxicity.

Other treatment plans may include maintaining your pup’s hydration by providing fluid in his bloodstream, medication for liver damage, and calling for blood transfusions in more serious cases.

You should not attempt to treat a case of onion toxicity by yourself. In certain cases, inducing vomiting can cause more harm than good, so it’s best to seek veterinary attention.

What Part of an Onion is Toxic to Dogs?

No specific part of an onion carries the toxin that is harmful to dogs — they’re in the whole thing! Onion Toxicosis can occur from the ingestion of:

  • Onion flesh
  • Onion juice
  • Onion leaves
  • Processed onion powder

This means that onions can cause harm to dogs if they are consumed even after they are cooked, fried, or powdered.

Onion powder is also in a surprisingly wide range of human foods, and it doesn’t take a lot of onion to get a dog sick.

For example, a 45-pound dog would only need to eat one medium raw onion to experience dangerous levels of toxicity. It’s difficult to keep a watchful eye on a dog at all times when food is out, but it is especially important if onions are involved.

Are All Onions Dangerous To Pets?

All onions whether cooked or raw or even free-dried are a danger to your pet. It takes a small amount of onions to poison your cat or dog, with cats being more sensitive to onion’s effect than dogs. Additionally, Japanese breed dogs (e.g. Akita, Shiba Inu, Japanese Chin) may be genetically more susceptible than other dog breeds.

Consumption of as little as 5 g/kg of onions in cats or 15 to 30 g/kg in dogs has resulted in clinically important red blood cell damage. Onion toxicosis is consistently noted in animals that ingest more than 0.5% of their body weight in onions at one time.

Please note that a pet’s weight, breed, and prior health history can vary the toxicity level of ingested onion.