Can dogs eat onions?

Written by Dr Andrew Miller MRCVSDr Andrew Miller MRCVS is an expert veterinary working in the field for over 10 years after graduating from Bristol University. Andy fact checks and writes for Pure Pet Food while also working as a full time veterinarian. Pure Pet FoodPure Pet Food are the experts in healthy dog food and healthy dogs featured in media outlets such as BBC, Good Housekeeping and The Telegraph. Working with high profile veterinary professionals and nutritionists, Pure Pet Food are changing dog food for the better. - Our editorial process

Onion toxicity is a real concern and can dramatically affect the health of your dog. If you think your dog has eaten any sort of onions (including foods in the same family e.g chives, leeks, shallots, garlic etc.), whether cooked, raw, powdered etc. consult a veterinary professional.

Are onions toxic to dogs?

Yes, onions are toxic to dogs, avoid feeding your dog onions.

Onions contain a toxin called N-propyl disulphide which is known to cause a breakdown of red blood cells in your dog resulting in anaemia. They also contain a substance called thiosulfate which dogs can’t digest and organosulfur which results in toxicosis. Ingesting onions could lead to not only anaemia (and haemolytic anaemia) but also liver damage, diarrhoea, vomiting, weakness, dermatitis and asthmatic attacks.

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Can dogs eat onions?

In short, no. All parts of the onion, including powders and leaves, are toxic to dogs. This also includes veg that’s part of the allium family such as garlic, shallots, chives and leeksJust like grapes, you should avoid onions no matter what, cooking onions doesn’t remove any of the toxicity and make sure any broth (including pre-made broth) doesn’t include onions.

Can dogs eat cooked onions?

No. Avoid cooked onions or any processed onions. Onion juice, powder and broth are still as harmful as raw onions.

Symptoms of eating onions as a dog

Symptoms can vary depending on the number of onions eaten by the dog, the size of the dog and how quickly the onions were eaten. If a small dog eating a lot of onions very quickly will have more severe symptoms than a large dog eating a small number of onions slower.

These symptoms could range from lethargy, pale gums, weakness, fainting, increased heart rate, decreased appetite, and even reddish urine.

If you see any of these consult a vet immediately. Even if you don’t see these it is always a good idea to visit your vet and have a check-up.

What should you do if your dog ate onions?

Consult your vet. It’s much better to be on the safe side of things and a vet will be able to catch these symptoms and treat accordingly much better than you can at home. Make sure you keep all onions away from your dog so they can’t eat any more and cause more harm as they’ll definitely try to.

Possible treatments from a vet include carrying out gastric lavage, flushing the stomach or inducing vomiting. If there’s a skin infection bathing may be necessary too. We can’t stress enough the importance of getting a vet’s opinion on this as each individual case will differ.

Your dog will be much happier with a delicious, and also nutritious meal, such as Pure, rather than a plate full of nasty onions. Pure is complete and balanced, tailored to your dog and totally natural with extra vitamins and minerals to ensure your dog gets every bit of goodness they need in their daily life.