Can Dogs Eat Onions? Here’s Why They Shouldn’t!

onions are toxic to dogs

Onions are a popular flavor to add to our dishes. Can you add it to your dog’s meals too? Can this pungent culinary cause more harm than bad breath or can dogs eat onions without any worries? The answer is yes, and this article explains why.

Onions are not simply bad for dogs. The risks in dogs eating onions can be fatal.

Familiarize yourself with the risks and actions you must take if you catch your dog eating onions by reading further below.

Can Dogs Eat Onions?

Dogs cannot eat onions because they are extremely toxic. This includes all the parts of the pungent culinary from the flesh to its leaves, the juice, and even the processed powders.

Beware of onion powder. You’d be surprised at the number of foods such as soups and even baby food containing onion powder. For this reason, you must always check the label of any human food that you are allowed to feed to your dogs. To be safe, always keep your human foods (i.e. chicken) unflavored and unseasoned when you feed them to your canine pal.

Can Dogs Eat Onion Rings?

Unlike raw meat, if you cook, fry, or powder onions, you will not get rid of their toxicity. Thus, dogs cannot eat onion rings, either. Be careful as most dogs do find the flavor of onion rings appealing. Given the opportunity, they will try to taste them.

Did you know? The entire allium family are toxic food to dogs. This includes onions, shallots, leeks, chives, and garlic.

Onion Toxicity in Dogs

Onion toxicity in dogs is dangerous, and it can be fatal. It leads to hemolytic anemia, which is an excessive breakdown and destruction of healthy red blood cells. Remember, red blood cells supply oxygen and remove carbon dioxide from the dog’s body.

Severe toxicity levels may begin taking effect once a medium-sized dog eats one medium-to-large-sized onion.

If you suspect that your dog has eaten onions, call a vet straight away.

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Symptoms of onion toxicity in dogs that you should watch out for include the following:

  • lethargy or loss of appetite
  • weakness
  • pale gums
  • fainting
  • blood in urine
  • vomiting
  • panting
  • increased heart rate

Tip: Use Cooper Pet Care’s pet symptom checker to check for symptoms in your dog and see the next steps that you need to follow.


Ideally, you should never give onions to your dog. In addition, you should also be mindful of any abandoned, onion flavored leftover dishes in your kitchen. Keep onions out of their sight.

Alternatively, if you catch your dog eating onions, they will need veterinary attention immediately. Call your vet right away. Depending on when your dog ate the onions, your vet may induce vomiting to expel it out of their body before its toxicity takes effect. Further, your vet will also offer any additional care that their body may need.

Onion toxicity can be lethal. In some extreme cases, dogs may even require a blood transfusion. Try to get them to your vet as fast as possible to avoid any long-lasting effects.

Final Words

Onions are toxic to dogs to the point where they can be lethal. Do not feed any to them, and do not try treating them by yourself if you catch them stealing an onion slice. Contact your vet right away and do not ignore any symptoms.

Alternatively, there are plenty of different human options for your dogs that you can try. Check out the healthy dog treats from human foods master-list for some inspiration!

A video consultation with one of Cooper Pet Care’s qualified veterinarians is also only a few clicks away. Fast, simple, and secure – get the answers you need.

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