Can Dogs Eat Onions? Why You Shouldn’t Feed Your Dog Onions

No, onions are a toxic food for dogs. In fact, all produce belonging to the Allium family (including scallions, chives, leeks, and shallots) as well as all parts of the onion (such as the stems and leaves) can harm your dog if consumed. Avoid feeding your dog raw onions, cooked onions, or onion rings. Take particular care to avoid feeding your dog onion powder or garlic powder, as these ingredients have concentrated doses of toxicity. The ASPCA considers dogs of Japanese breeds (like Shiba Inus and Akitas) to be especially vulnerable.

All members of the Allium family of plants contain a compound called N-propyl disulfide. Since dogs lack the enzyme required to properly digest it, the sulfur compound in N-propyl disulfide can bond to the hemoglobin protein in a dog's red blood cells, causing a lack of oxygen distribution through the blood and an overall breakdown of red blood cells known as hemolysis. The cells then form clusters called Heinz bodies. The dog's body identifies the Heinz bodies as harmful and will work to eradicate them. If this oxidative damage continues, it causes hemolytic anemia, or a reduction of red blood cell count at a faster rate than their reproduction.

If your dog regularly eats even small amounts of onion, the consequences can build up over time. Though not usually life-threatening if treated early, the buildup of N-propyl disulfide can exponentially worsen. Delays in treatment can create severe cases of poisoning, which require medically administered oxygen or blood transfusions.

Learn the general symptoms of onion toxicity so you know how to spot the signs in your dog.

1. 1. Elevated heart rate: The hemolysis caused by the ingestion of the sulfur compound in onions reduces the oxygen-carrying capabilities of red blood cells. Your dog may exhibit an elevated respiratory rate and an increased heart rate to try to make up for the lack of oxygen.
   
2. 2. Lethargy: A lack of oxygen can make dogs tired. This is a common symptom of anemia and can show up soon after your dog ate onions but can also start a few days after.
3. 3. Pale gums: Pale gums are a sign that toxicosis has already caused an anemic reaction, and in general, it's good pet health practice to notice pale gums as a sign something is awry. Call your vet to perform blood work if your dog’s gums aren't pink, to determine if there's an anemic issue.
4. 4. Abdominal issues: Any unusual and recurring digestive symptoms like vomiting, loss of appetite, or diarrhea can occur with onion poisoning.

It’s fine to occasionally feed your dog human food in addition to pet food. Vegetables that are suitable as dog treats include cucumbers, carrots, celery, and broccoli. Brussels sprouts and cabbage are also great, though over-feeding can cause your dog to become gassy. Green beans are great and can be easily mixed into dog food; however, watch the salt content if feeding your dog green beans from a can, as too much sodium can lead to other health issues.

Certain human foods can cause adverse reactions in canines, so always consult your veterinarian to determine whether it is safe to add these foods to your pet’s diet. This article is for educational and informational purposes and is not a substitute for medical or dietary advice.

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