The Truth About Onion and Garlic Toxicity in Dogs

Estimated Reading Time 3 minutes
The Truth About Onion and Garlic Toxicity in Dogs

Garlic and onions are from the same family, Liliaceae, and are toxic to dogs, cats, and horses. The toxic component is N-propyl disulfide and other sulfur-containing oxidants (SCO). Cats are the most sensitive and develop more severe symptoms. Continue reading to learn about the symptoms and treatment of garlic and onion toxicity in pets.

Are you concerned about your pet?

Book a video consultation with an experienced veterinarian within minutes.

  • Professional vet advice online
  • Low-cost video vet consultations
  • Open 24 hours a day, 365 days a year

Can my dog eat onions and garlic?

All parts of the onion and garlic plants are considered toxic to pets. Dried onions and garlic used for cooking are also toxic and since they are dried, more of the toxins are present in smaller volumes. Don’t forget a lot of broths, baby foods, and soups contain onions and garlic, so be sure to read the ingredient lists carefully before you share this with your pets.

Clinical Symptoms of Onion and Garlic Poisoning in Pets

Clinical symptoms typically develop within 24 hours, but they can be delayed for up to 7 days after the food has been ingested.

Why do onions and garlic cause these symptoms in dogs?

The toxic component of onions and garlic, N-propyl disulfide and other SCO’s, attach to the oxygen molecule of the body’s red blood cells. This makes the body see the red blood cells as a foreign invader, and the immune system starts to attack the damaged red blood cells.

This reduces the body’s ability to carry oxygen to the organs and tissues. Since the body is now oxygen-deprived, your pet will be weak, pant more trying to get more oxygen exchanged in the lungs, and increases the heart rate as the body tries to find ways to move oxygen around.

What should I do if my dog ate onions or garlic?

If you know your cat or dog ingested garlic or onions, you should take them to the vet to induce vomiting. This will remove as much of the toxins as possible. Making the pet vomit is best done if ingestion was in the past 1-2 hours or less, otherwise, it’s likely out of the stomach and moved into the intestines.

If your pet ate onions or garlic and now has red or brown urine, is weak, panting or breathing faster than usual, bring them to the vet immediately. They may need oxygen supplementation, a blood transfusion, and IV fluid support to get them through this. Remember, some of these symptoms can take a week to develop!

Some other toxins and diseases can cause similar symptoms and anemia, so your vet may need to run additional tests to be sure nothing else is contributing or causing your pet’s symptoms.

Read more:

Can dogs eat onions?

Onion, Garlic, Chive, and Leek Toxicity in Dogs

Need to speak with a veterinarian regarding your dog and garlic toxicity or another condition?

Click here to schedule a video consult to speak to one of our vets. You can also download the FirstVet app from the Apple App Store and Google Play Stores.

Published: 11/14/2020
Last updated: 11/18/2021

Are you concerned about your pet?

Book a video consultation with an experienced veterinarian within minutes.

Get started
  • Low-cost video vet consultations, 24 hours a day Low-cost video vet consultations, 24 hours a day
  • Experienced, licensed vets Experienced, licensed vets
  • Over 700,000 satisfied pet owners Over 700,000 satisfied pet owners
Low cost consultations, 24 hours a day.Low cost consultations, 24 hours a day.

With FirstVet, the vet clinic and pet shop are only one tap away. Get fast advice, trusted care and the right pet supplies – every day, all year round.


FirstVet Inc

900 3rd Ave 29th Floor


New York