Can Dogs Have Onions?

No. Dogs can not have onions.

Although perfectly healthy for humans, feeding onions to dogs, whether raw, cooked or powdered, can be very dangerous and cause your dog harm.

Why are onions poisonous to dogs?

Onions contain a compound called N-propyl disulfide which can damage your dog’s red blood cells and cause anaemia.

According to the ASPCA & AKA, potential signs of onion poisoning in dogs include:

  • Vomiting
  • Blood in urine
  • High heart rate
  • Weakness
  • Pale gums
  • Lethargy
  • Decreased appetite

If your dog has any of these symptoms after eating onions and you are concerned, speak to your vet immediately.

It’s not just onions either…

All members of the allium family are potentially harmful. This includes garlic, leeks shallots and chives.

Treatment if your dog has eaten onions

The best way to prevent onion poisoning is not to allow your dog to eat them in the first place. Accidents do happen though.

Should your dog require treatment, speak to your vet immediately.

Treatment will range from induced vomiting, to a blood transfusion in more serious cases. Speak to your vet and let them guide you.

Can dogs eat cooked onions?

No. Cooking does not destroy the compound.

Onion is dangerous in all its forms, including raw, cooked and powdered.

This includes more obvious foods like fried onions, onion rings and the not so obvious, like meatloaf, chicken broth etc, where the onion is usually in powder form.

As onion powder is so concentrated, this can be especially dangerous.

Onion powder is found in many human food products, so it is vital that you check the ingredients of these before feeding any to your dog.

This is a good reason why it’s good practice not to feed them any scraps whatsoever and just stick to their dog food and snacks.

How much onion will kill a dog?

According to the American Kennel Club, as little as 100 grams of fresh onion per 20 kilos of dog weight can cause toxic effects.

To put that into context, a fully grown female Labrador’s weight starts at around 20 kg. If she ate 1 medium raw onion, she would be at risk of onion toxicity.

Now this all depends on your dog’s tolerance, weight and other factors, but you can see how it could quite easily happen, especially with a dog as greedy as a Labrador!

Raw onions aren’t usually at the top of a dog’s list to eat, but you never can tell with dogs sometimes. They can eat the strangest things!

Onion poisoning can be fatal, so seek advice immediately.


If you are worried that your dog has eaten a dangerous amount of onion, speak to your vet immediately.

If your dog has only eaten a very small piece of onion, then depending on its size, it will probably be fine. Get some professional advice to be sure though.

Better safe than sorry!

Related: Can Dogs Eat Radishes?