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Can Dogs Eat Green Onions? Why Are They Bad?

Dogs can not eat green onions. These are toxic to dogs, like all other vegetables in the onion family. If eaten, dogs can experience onion toxicity, a state where red blood cells are destroyed. This can be fatal.

Dogs use their mouths to explore new things, and it’s natural to wonder if something is safe for them to eat. Green onions are a common ingredient in many dishes, but can dogs eat green onions?

We did some digging to find out the nutritional value of green onions for dogs and whether or not they are safe to eat. 

Read on for everything you need to know about feeding your pup green onions!

Can Dogs Eat Green Onions?

No, dogs cannot eat green onions. Green onions are a member of the allium family of vegetables, which also includes garlic, leeks, and chives. These vegetables contain compounds that are toxic to dogs and can make them very sick.

Onions are toxic to dogs, including green, yellow, white, and other forms. 

Symptoms of onion toxicity in dogs include[1]:

  • Vomiting
  • Diarrhea
  • Abdominal pain
  • Lethargy

If your dog has eaten green onions, call your veterinarian or animal poison control immediately. Treatment will likely involve giving your dog IV fluids and other medications to help them feel better.

Are Green Onions Safe for Dogs to Eat?

Green onions are not safe for dogs to eat. While they are safe for humans to eat, green onions contain a substance called thiosulfate which can be harmful to dogs.

Green onions, also known as scallions, are a type of onion that has a milder flavor than other types of onions. The milder flavor has no correlation to their toxicity, as green onions still have thiosulfate in them.

Thiosulfate is a toxic compound that can cause gastrointestinal irritation and vomiting in dogs[2]. In severe cases, thiosulphate can lead to kidney damage or even death.

For this reason, it is important to keep green onions out of reach of your dog. If your dog does eat too many green onions, it is important to seek veterinary care immediately.

Are Green Onions Safe for Dogs to Eat

Are Green Onions Bad for Dogs?

Yes, green onions are bad for dogs. While ingesting small amounts most likely won’t cause many problems, high amounts can be lethal.

Aside from thiosulfates, green onions contain sulfoxides which are toxic to dogs. These substances can damage a dog’s red blood cells and cause anemia. The toxicity is more severe in young dogs, puppies, and small breeds.

Can Dogs Eat Shallots?

Dogs can’t eat shallots. Shallots are poisonous to dogs. If your dog eats too many shallots, it will likely experience gastrointestinal distress and may need to be hospitalized.

Symptoms of shallot poisoning in dogs include vomiting, diarrhea, and abdominal pain. In severe cases, seizures and death may occur. If you think your dog has eaten an excessive amount of shallots, please contact your veterinarian or the ASPCA poison control center immediately.

Can Dogs Eat Shallots

What Do Onions Do to Dogs?

Onions are a common ingredient in many dishes, but they can be dangerous for dogs. Onion poisoning in dogs can cause gastrointestinal irritation and anemia.

Symptoms of onion poisoning in dogs include vomiting, diarrhea, lethargy, and difficulty breathing. If your dog has eaten onions, contact your veterinarian immediately.

Treatment for onion poisoning in dogs depends on the severity of the symptoms. Onion poisoning is preventable, so make sure to keep onions out of your dog’s reach.

sick dog on vet clinic

What to do if your Dog eats Onion?

If your dog eats onion, there is no need to panic. Although onions are toxic to dogs, the danger is mainly from eating large amounts. In most cases, if your dog only eats a small amount of onion, there will be no ill effects.

If your dog does eat a significant amount of onion, there are a few things you can do to help minimize the damage.

  1. First, try to induce vomiting. You can do this by giving your dog hydrogen peroxide or a saltwater solution. If your dog doesn’t vomit within 15 minutes, take him to the vet.
  2. The vet will likely give your dog activated charcoal to absorb any remaining toxins. He may also give your dog IV fluids to prevent dehydration. In severe cases, a blood transfusion may be necessary.
  3. Most dogs will recover just fine if they receive prompt treatment. However, if you’re at all concerned, it’s always best to err on the side of caution and take your dog to the vet as soon as possible.

How Many Green Onions Can Dogs Eat?

Dogs cannot eat any green onions because they contain a toxin called thiosulphate which can cause vomiting and diarrhea. While small amounts of this toxin may not cause any problems, large amounts can be deadly.

Green Onions Alternatives for Dogs

Dogs are carnivores and green onions are not a part of their natural diet. Aside from abdominal pain, they can cause gastrointestinal upset including diarrhea and vomiting. 

There are plenty of other healthy, safe alternatives to feeding your dog green onions. Some good substitutes for green onions include

All of these vegetables are safe for dogs and are full of healthy nutrients like vitamins, minerals, and antioxidants. They are also low in calories and easy for dogs to digest.

If you want to give your dog a healthy, onion-free snack, try giving them one of these vegetables instead. Your dog will love the taste and you’ll know they’re getting the nutrients they need.


Dogs can’t have green onions. If you want to share your food with your companion, make sure it doesn’t include any onions. Dogs exposed to onions should be monitored. If you notice any symptoms of onion poisoning, contact your vet.

All vegetables of the onion family should be avoided.


How Much Green Onion is Toxic To A Dog?

100 grams of green onion can be toxic to a dog. They contain thiosulphate, which is toxic to dogs in large amounts. Onions, garlic, chives, and leeks are all part of the Allium family. Green onions have a higher concentration of thiosulphate than other onions. It only means that they are more dangerous to dogs.

Can Dogs Eat Little Green Onions?

No, dogs cannot eat little green onions. Scallions are not safe for dogs to eat. Ingesting even a small amount of onion can cause gastrointestinal upset in dogs. In severe cases, ingestion of onions can lead to anemia in dogs.

How Long After Eating Onions Will A Dog Get Sick?

It takes 1 to 3 days for symptoms to show. If your dog has eaten onions, keep an eye out for signs of illness. These can include vomiting, diarrhea, lethargy, and a lack of appetite. If your dog shows any of these symptoms, contact your veterinarian right away. Treatment will likely be needed to prevent serious health problems.

About Dennis Stapleton

Dennis Stapleton has a passion for animals, especially dogs, and their relatives. He’s intrigued by their social structure and loves to write and teach about the world's most popular pet animal.