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Help! My Dog Ate Onions

Wooden spoon full of chopped onion with 3 whole onions on table and basket of onions in background.

There are a lot of human foods that are toxic to dogs and onions are among the most dangerous ones. Irrespective of the form they are in (raw, cooked, or powdered), feeding your dog onions will make him/her seriously ill.

Why Onions are Poisonous for Dogs?

The chemical that makes onions unsuitable for dogs is a sulfur compound called thiosulfate. Canines don’t have an enzyme to digest this antioxidant. Given the low antioxidant capacity of canine red blood cells, this substance will be catastrophic for them.

Consequently, a large number of red blood cells are destroyed and hemoglobin is deactivated. This will decrease the overall ability of the blood to deliver oxygen to the dog’s body. Medically, this condition is called Hemolytic Anemia.  

If your dog eats onion, you should always call your vet or the pet poison control line at: (888) 426-4435

Symptoms of Onion Poisoning

German shepherd laying on vet exam room floor receiving IV

Other than the smelly breath, the signs of onion poisoning do take 1-3 days to appear. Some of these symptoms are listed below.

  • Vomiting
  • Diarrhea
  • Weakness
  • Tachypnea
  • Tachycardia
  • Lethargy
  • Pale or bluish gums
  • Yellow eyes
  • Collapse

Treatment of Onion Poisoning

Puppy being examined by vet

It is extremely important to contact your vet as soon as you observe signs of onion ingestion in your dog. If the poisoning is detected early, the toxic effects can be controlled by inducing vomiting and using activated charcoal. The charcoal can also be used to treat allergic reactions, like a skin infection. After the initial treatment, the vet may instruct you to look for symptoms of anemia over the next few days.

In extreme cases, IV fluids will be used to keep the body of your pet hydrated. Similarly, supplemental oxygen, liver therapy, and blood transfusions might be needed to stabilize your dog. For these treatments, your companion might have to spend some days in a veterinary hospital.   

My Dog Ate Green Onions

bunch of green onions on wood surface

Also known as Scallions, green onions have a milder taste than onions. Despite the change in flavor, green onions are also toxic to dogs. Having said that, small quantities of green onions might not cause much harm to your dog. However, an upset stomach and loss of appetite will suggest that your canine friend is uncomfortable. If these symptoms continue to persist for a few days, you must seek professional help.

The toxicity of onions is directly proportional to the amount consumed. For instance, 100 grams of green onion can cause toxic effects in your dog if he/she weighs around 45 pounds. 

My Dog Ate Meat Cooked with Onions

steak with sauteed onions surrounded by herbs and garnishes on wooden surface.

Dogs are extremely curious animals who love eating. As a result, they won’t mind taking a bite from your plate. Therefore, it is essential to make sure that your pet is NEVER exposed to a meal with onions in it. Some people believe that the toxic effects of onions are canceled out when they are cooked. Unfortunately, that’s NOT true and a cooked onion is equally dangerous for your dog.

Actually, the toxin (found in onion) is not limited to a specific part of the vegetable. Instead, it is present in all the parts including flesh, leaves, juice, and even powder. For this reason, the meat cooked with onion is poisonous for your canine friends.

My Dog Ate Onion Rings

fried onion rings on wooden surface with small bowl of ketchup.

Being a part of the Allium plant family, onions are not safe for your dogs. For this reason, you can’t share your favorite snack (onion rings) with your canine companion. Even if your dog is not showing any stressful symptoms after consuming an onion ring, you should consult your vet.

On the other hand, if your dog shows signs of onion toxicity, you should immediately take him/her to a vet. In severe cases, any kind of delay can lead to a life-threatening experience.

The number of onions consumed and the size of your dog will determine the extent of toxicity. According to an estimate, the canines that eat more than 0.5% of their body weight are likely to experience onion poisoning. Going by these calculations, a single onion ring won’t cause much harm to a 50-pound dog. Having said that, it is highly recommended to keep a close eye on your pets.   

My Dog Ate Onion Powder

wooden bowl of onion powder on an orange background.

Knowing the fact that all parts of the onion plant are toxic for dogs, your canine shouldn’t eat onion powder. In fact, it has been found that onion and garlic powders are more dangerous than fresh vegetables.

Onion powder is used in a wide range of edibles, ranging from soups to baby foods. In these circumstances, you MUST always check the ingredients list of human foods before giving them to your dog. Similarly, feline owners should also avoid onion treats because they are even more toxic to cats (than dogs).  

My Dog Ate Minced Onion

Dried minced onion on white background.

Chicken broth is one of the most popular dog foods around the world. It is easy to make and can be used with several other items, like rice. It is pretty common for people to share their broth with the pet. Although it is a convenient alternative, it can have a horrific drawback.

A lot of people use minced onions to add flavor and aroma in their broth. Likewise, the ready-made broth you purchased can have onions in it. Sharing such a broth with your canine companion can be troublesome for him/her. Therefore, always read the labels and purchase the broth that is free from onions.    

My Dog Ate Onion Soup Mix

package of Lipton Recipe Secrets Onion soup mix

Just like all the other forms of onion, a soup mix with onions is also harmful to dogs. Once again, the dosage of the soup mix will be critical for determining the severity of the onion poisoning. If a smaller quantity is consumed, mild symptoms (diarrhea and appetite loss) will be observed. A light diet, like rice and chicken, can be used to treat your dog if these signs appear.

On the other hand, too much onion soup mix will cause anemia and distressed breathing. In such cases, professional help and hospitalization will be needed to revive your pet.

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