Can Dogs Eat Onions? We’ve All Heard the Warnings…

We’ve all heard it before… there are several foods that dogs shouldn’t eat. Grapes, chocolate… And at the top of the list? Onions. Those flavorful bulbs we add to so many dishes for ourselves…

We’ve all come to know that onions are an issue for our dogs. Can dogs eat onions? They shouldn’t. But why? And what happens if your dog does get into them?

It’s time to peel back the basics on this popular root vegetable…

Can Dogs Eat Onions?

Can dogs eat onions? No, let’s start by saying that onions are one of the few foods that should never make their way into your dog’s bowl. Not only do they provide no nutritional benefit to our pups, but they can have potentially deadly effects. The same goes for the other members of the onion family – shallots, leeks, and chives.

Why? Well, onions contain a toxic compound called N-propyl disulfide. While this compound isn’t harmful to us, when your dog ingests it, it causes oxidative damage to the red blood cells by attaching to the oxygen molecules in them. This reduces the ability of those red blood cells to carry oxygen, and also tricks your dog’s body into thinking that the blood cell is an invader. The red blood cell is destroyed in a process known as hemolysis, resulting in hemolytic anemia.

All parts of the onion plant are toxic to dogs, including the flesh, leaves, and juice. These all contain that troublesome N-propyl compound. And no, cooking onions doesn’t get rid of it. Cooked onions are still toxic. In fact, all forms of onion can be toxic to dogs – raw, cooked, dried, even processed powder.

[RELATED] We mentioned xylitol earlier – have you heard of it? If not, you need to read this!! It’s important.

How Much Onion is Toxic?

The N-propyl in onions is what makes them a problem, but unlike something like xylitol, for example, onion toxicity depends on how much onion a dog eats, and how big your dog is. Typically, if your dog ingests only a small amount of onion, it shouldn’t cause any problems. That said, keep in mind that a small amount of onion will be more of a problem for 5lb dog than a 100lb dog.

As far as amounts though, sometimes it helps to have a number: about 100 grams of onion (about the size of a medium onion) per 20 kilograms of a dog’s weight can cause toxic effects. So, if you’re cooking something with onion and drop a small slice on the floor, this isn’t likely to make your dog sick. But, if your 45lb dog eats a full medium-large size onion, that would be a dangerous amount.

If you think your dog may have eaten onions, here are the symptoms to watch for:

• Lethargy
• Weakness
• Vomiting
• Decreased appetite
• Elevated heart rate
• Pale gums
• Fainting
• Increased panting
• Reddish urine

Not sure how much your dog ate? If there’s a chance it was a significant amount, it never hurts to contact your vet.

If your dog has eaten a toxic amount, veterinary care will be required. Your veterinarian may induce vomiting, depending on how recently your dog ate the onions, and will offer supportive care until your dog’s body can produce enough healthy red blood cells to replace the damaged ones. In severe cases, your dog may require a blood transfusion.

So, we know well that the answer to “can dogs eat onions” is no – and while the amount matters, it’s always just safest to keep them away. Watch the ingredients in any foods you share with your pet and keep onions in a secure spot your dog can’t access. If your dog does get into them, and you have a concern or she doesn’t seem to be acting herself, head to the vet.