can dogs eat onions safely?

Onions and Dogs: Deadly Mix?

Onions are a staple in kitchens worldwide, adding flavor to countless dishes. From raw slices in salads to caramelized goodness on burgers, their versatility is undeniable. But what about our canines?

Can dogs eat onions safely?

Unfortunately, the answer is a resounding no. Onions are toxic to dogs, ranking high alongside grapes and raisins on the list of forbidden foods. Even small amounts can have serious consequences.

Here’s why onions pose a threat:

  • Hidden Danger: The culprit behind onion toxicity is N-propyl disulfide, a sulfur-based compound responsible for the vegetable’s pungent aroma. This very same compound wreaks havoc on a dog’s red blood cells.
  • Anemia on the Horizon: N-propyl disulfide damages red blood cells, leading to a condition called Heinz body anemia. This reduces the ability of red blood cells to carry oxygen throughout the body, potentially causing significant health problems.
  • Swift Action, Crucial Care: Symptoms of onion poisoning can appear quickly. If you suspect your dog has ingested onions, immediate veterinary attention is critical. Early diagnosis and treatment can prevent serious complications, but it can also be expensive.

Prevention is Key:

The best approach is to keep onions entirely out of your dog’s reach. This includes scraps from meal prep, uneaten leftovers, and even decorative onion rings displayed in bowls. By understanding the risks and taking preventative measures, you can keep your canine companion safe and healthy.

Common Sources Of Onion Exposure

As you most likely already know, dogs are very opportunistic eaters.  They will grab anything they can and devour it as fast as possible if you’re not paying attention.  Even a freshly fed dog will take advantage when it sees something easily accessible.  That is why it is critical to keep onions away from dogs. This actually pertains to anything in the allium genus, they are all toxic to dogs.

Dogs will not commonly eat whole onions.  They will however eat onion rings, foods with onion powder, casserole dishes, and many other prepared foods.   It is best to keep your dog away from anything that contains onions, keep it out of reach.  

onions are harmful to dogs

Symptoms Of Onion Toxicity In Dogs

The symptoms can start in as little as an hour depending on many factors.  The size of the dog, the breed, the amount that was eaten, and what was eaten are all factors that influence the onset of symptoms.  A majority of dogs that eat onions will start with GI issues.  Expect to see the following:

  • Vomiting
  • Diarrhea
  • Loss of appetite

If left untreated, which is totally not recommended, Heinz body formation starts within 24 hours and peaks by the 72nd hour.  Clinical signs of anemia can start in as little as 3 to 7 days.  It is possible you will see these additional symptoms if your dog has anemia. They may show only a few of the symptoms, in more severe cases you can expect to see most of the symptoms below.

  • Panting
  • Pale gums
  • Fainting
  • Increased heart rate
  • Difficulty breathing

 It goes without saying, but if your dog was exposed to a large number of onions and has any of the above symptoms you should contact your vet immediately.  The sooner you act the better the outcome will be for your pet.

Treatment For Onion Toxicity In Dogs

So the good news, is if your dog ate onions, it can be treated.  It is best to take your dog to the vet to have it properly evaluated. The first concern would be dehydration if your dog has been vomiting or having loose stools.  The vet may want to keep the dog overnight even if it does not have symptoms of anemia just to monitor hydration.  They may even opt to put your dog on an IV drip. 

Depending on how much onion was eaten, there are a few different things that can be done to reduce the damage that onions cause.  They can clean out the GI tract via an enema, they can use active carbon, and they can also use a solution of diluted hydrogen peroxide to induce vomiting.  Even though active charcoal is listed as a treatment, there is not really any evidence that shows it does anything.  

Can Dogs Eat Onions FAQ

Can dogs eat onions cooked?

No, dogs can not eat cooked onions. It turns out that cooking the onions does not in any way reduce how toxic they are to your dog.  Sautéed onions are just as toxic to your dog as raw onions.  Depending on how they are cooked they might be more tempting to your dog as well.   

What are the symptoms of onion poisoning in dogs?

Onion poisoning in dogs typically starts with GI-related symptoms.   Expect to see some vomiting and diarrhea followed by a loss of appetite.  If the dog consumed a large number of onions then you can expect anemia 3-7 days afterward.  You should immediately seek help from a veterinarian if your dog ate a lot of onions.  

How much onion is toxic to dogs?

According to a few studies, it takes a ratio of between 15-30grams per KG of body weight of the dog.   A single medium onion weighs about 175 grams.   So on the high side, 1 medium onion could cause symptoms in a dog that weighs 11 kg.  Smaller dogs take less onion to cause damage than larger dogs.   

How to treat onion poisoning at home?

I would say unless you’re a vet don’t be stupid and try home remedies.  Do not try to treat your dog at home for onion poisoning!  You are essentially playing with your pet’s life at this point.  If your dog consumed enough to be at a toxic level, call a vet immediately.  If you are unable to get to a vet for unforeseen reasons you should induce vomiting in the dog to help rid the dog of the toxic onions. This is especially critical that it is done within 2 hours of consumption.

Is one onion ring going to hurt my dog?

As scary as it might be if your dog ate only one onion ring it should be clinically ok.  It’s possible you will see some GI upset due to the fact that it is part of the allium genus and the oils from frying.  I would be more concerned that the dog vomits since it can not process fats very well.

Will a tiny piece of onion hurt my dog?

If your dog only ate a small piece of onion it is very unlikely that you will see any ill effects.  As long as your dog ate less than 10g/kg of body weight, it should be ok.  Once it approaches 15G/Kg of body weight, you could see some negative side effects.   

What to do if the dog ate a small piece of onion?

If your dog ate a small piece of onion there is most likely nothing that needs to be done.  However, if you have a small dog and the ratio exceeded 15g/kg of body weight, the dog should be seen by a veterinarian.  At this level, it is best to have the dog seen by a vet within 2 hours.  Typically if the dog ate enough onion to be toxic, the vet may want to induce vomiting.  Some veterinarians may also give active charcoal after the induced vomiting, There does not seem to be any evidence that supports that as being a treatment.  

Summary: Can dogs eat onions?

  • Dogs should not eat onions
  • Dogs should be seen by a vet within 2 hours of eating onions if a large amount was eaten
  • Small amounts of onions will not hurt a dog
  • The first signs of onion toxicity are vomiting and diarrhea, followed by panting, difficulty breathing, and rapid heart rate.  
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Has your dog ever been exposed to a large number of onions?  What did you do? Please leave a comment below.  

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