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Pawrennial

Can dogs eat onions?

No.

Onions damage a dog's red blood cells and can cause anemia. Raw, cooked, fried, and dried onion are all harmful, and onion powder is the most concentrated. Problems often show up several days later.

Did your dog just eat onions?

Call your vet or a pet poison line for advice, especially if your dog ate a lot, ate onion powder or soup mix, or is small. Signs can take days to appear.

Call your vet, an emergency vet, or a 24/7 pet poison line:

US numbers. A consultation fee may apply. Don't try to make your dog vomit unless a vet tells you to.

Can dogs eat garlic?Garlic is in the same family and is even stronger.

Why are onions bad for dogs?

Onions belong to the Allium family, along with garlic, leeks, chives, and shallots. They contain sulfur compounds that damage red blood cells, which then break apart. If enough are destroyed, your dog becomes anemic: their blood can't carry enough oxygen.

Cooking doesn't make onions safe. Dried and powdered onion, like in soup mixes, gravy, and seasoning, is the most concentrated and the most common cause of poisoning in dogs.

How much onion is toxic to a dog?

The Merck Veterinary Manual reports signs in dogs that ate 15 to 30 g of raw onion per kg of body weight. That's roughly a medium onion for a 20 lb dog. Smaller amounts eaten every day, like table scraps, can also add up over time.

Because onions vary and some foods contain concentrated powder, don't try to work out a safe amount. If your dog eats onion, call your vet for advice.

Signs of onion poisoning

Changes in the blood start within a day, but signs of anemia usually appear 3 to 5 days later. An upset stomach can come first. Watch for:

  • Vomiting, diarrhea, or drooling
  • Tiredness, weakness, or not wanting to exercise
  • Pale or yellow gums
  • Fast breathing or a fast heartbeat
  • Red or brown urine
  • Collapse (an emergency)

What the vet will do

If your dog ate onion recently, your vet may make them vomit to empty the stomach. They may check your dog's blood over the next few days. Dogs with severe anemia can need oxygen, fluids, or a blood transfusion. With treatment, most dogs recover as their body makes new red blood cells.

Foods that hide onion

  • Gravy, stock, and bouillon
  • Soups and dry soup mixes
  • Pizza, burgers, meatloaf, and stuffing
  • Baby food (check the label)
  • Seasoning blends and onion powder
  • Takeout and table scraps

Helpful tools and guides

Frequently asked questions

My dog ate a small piece of onion. Should I worry?

A tiny piece is unlikely to harm a large dog, but there's no reason to wait and see. Call your vet or a poison line, especially for small dogs, large amounts, onion powder, or if your dog eats onion regularly. They can tell you whether treatment is needed.

Are cooked onions safe for dogs?

No. Cooking, frying, or drying onions doesn't destroy the compounds that harm red blood cells. Dried onion and onion powder are actually more concentrated.

How long does onion poisoning take to show?

Stomach upset can happen within a day, but anemia usually develops 3 to 5 days after eating onion. That's why a vet may want to recheck your dog's blood even if they seem fine at first.

Are leeks, chives, and shallots also toxic?

Yes. They're all in the Allium family with onions and garlic, and can damage red blood cells in the same way. Keep them all away from your dog.

Can cats eat onions?

No. Cats are even more sensitive to onions than dogs. Merck reports problems in cats after less than a teaspoon of cooked onion.

Sources

Sources last checked: . How we calculate

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