Are Onions Toxic to Pets?
Yes — onions are toxic to cats. Yes — onions are toxic to dogs. Yes — onions are toxic to horses.
PawSafe Check is for general information only and is not veterinary advice. Always contact your veterinarian or a poison control service if you think your pet has been exposed.
- Scientific name
- Allium cepa
- Toxic compound
- Organosulfur compounds (N-propyl disulfide)
- Toxic parts
- Raw, cooked, powdered and dehydrated onion
- Also known as
- onion powder, red onion, shallots
Symptoms
Cats (toxic)
- Vomiting
- Diarrhea
- Weakness or low energy
- Pale gums
- Fast breathing or heart rate
- Red or brown urine (anemia can appear several days later)
Dogs (toxic)
- Vomiting
- Diarrhea
- Weakness or low energy
- Pale gums
- Fast breathing or heart rate
- Red or brown urine (anemia can appear several days later)
Horses (toxic)
- Vomiting
- Diarrhea
- Weakness or low energy
- Pale gums
- Fast breathing or heart rate
- Red or brown urine (anemia can appear several days later)
What to do
If your cat ate onions
- Call your vet or a pet poison control line immediately — don't wait for symptoms.
- Do not induce vomiting unless a vet tells you to.
- Bring the plant, label or packaging with you so the vet knows exactly what your cat ate.
- Note roughly how much was eaten and when.
If your dog ate onions
- Call your vet or a pet poison control line immediately — don't wait for symptoms.
- Do not induce vomiting unless a vet tells you to.
- Bring the plant, label or packaging with you so the vet knows exactly what your dog ate.
- Note roughly how much was eaten and when.
If your horse ate onions
- Call your vet or a pet poison control line immediately — don't wait for symptoms.
- Do not induce vomiting unless a vet tells you to.
- Bring the plant, label or packaging with you so the vet knows exactly what your horse ate.
- Note roughly how much was eaten and when.
Good to know
Onion damages red blood cells and can cause anemia. Onion powder in baby food, gravy and seasonings counts too. Cats are especially sensitive.
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Frequently asked questions
Are onions toxic to cats?
Yes — onions are toxic to cats. Common signs include vomiting, diarrhea, weakness or low energy.
Are onions toxic to dogs?
Yes — onions are toxic to dogs. Common signs include vomiting, diarrhea, weakness or low energy.
Are onions toxic to horses?
Yes — onions are toxic to horses. Common signs include vomiting, diarrhea, weakness or low energy.
Which parts of onions are toxic?
Raw, cooked, powdered and dehydrated onion.
What makes onions toxic?
Organosulfur compounds (N-propyl disulfide).