a dog holding an onion
Can Dogs Eat Vegetables?

Can Dogs Eat Onions?

How delicious are onions? Whether roasted, raw or caramelized, they’re practically a must in a human diet, and bring a lot of benefits. If you’re an onion lover (and even if you aren’t), you might have asked yourself if your pup can also benefit from this amazing veggie… Can dogs eat onions? Let’s find out!

Can dogs eat onions?

No, they can’t. Unfortunately, dogs do not benefit from onions as humans do. Onions are highly toxic for dogs, and they should never be offered to our canine companions.

The mechanism of onion toxicity has been well-known for quite some time – decades, even – and involves more than one toxin. The presence of substances like sulfoxides and aliphatic sulfides, specifically allyl and propyl di-, tri-, and tetrasulfides, make them harmful for pups. Onions specifically cause damage to dogs’ red blood cells, leading to haemolytic anemia along with the formation of Heinz bodies.

Heinz body anemia is not a common finding in dogs. This type of anemia makes your dog’s immune system “think” that red cells are invaders, causing it to start attacking and destroying them. This is a life-threatening condition, because the ability of your dog’s red cells to transport oxygen throughout the body is compromised.

What are the signs of toxicity?

The first symptoms are usually of digestive problem: vomits, diarrhea, abdominal pain, lack of appetite and dehydration.

After a few days, the symptoms of loss of red blood cells start to appear. Those include pale mucous membranes, high respiratory rate, difficulty to breath, lethargy, dark coloured urine, weakness, and rapid heart beating.

What to do if my dog ate onions?

Dogs can become sick if they consume as little as 15 to 30 g/kg of body weight, which means that one good-sized onion can make a 50lb dog ill.

This toxicity could be fatal if there is no medical support. So, the first thing to do is to call your vet. Depending on how recently your dog ate the onions, it may be necessary to induce vomit – but only in the presence of the vet, or with their instruction. Supportive care is necessary until the production of new healthy red blood cells is enough. In severe cases, a blood transfusion could be needed.

Remember – all forms of onion can be a very serious problem. Keep this veggie away from your cutie-pie!



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