Onion and garlic poisoning in dogs – signs and care

Updated 2026-09-30 · 1 sources

Based on: PDSA

Book a vet visit

Book a vet appointment if you think your dog has this – a vet needs to confirm it and plan the treatment. It is a form of poisoning involving onions and garlic.

What you can do now

  1. Contact your vet as soon as possible
  2. Note when it started, how often it happens and what else you see
  3. Take a photo or short video to show the vet
  4. Keep fresh water available
  5. Let your dog rest somewhere calm

Don't

  • Do not give any human medicine
  • Do not try to make your dog vomit at home
  • Do not wait if it gets worse

What it is

Onions and garlic are toxic to dogs.[1] Signs can include vomiting, diarrhoea, a sore abdomen, reduced appetite and dehydration.[1]

Signs

  • Vomiting
  • Diarrhoea
  • Sore abdomen (belly)
  • Reduced appetite
  • Dehydration

How a vet finds out

  • Blood tests

How vets treat it

  • Fluids or a drip
  • Hospitalisation
  • Medication

What the experts say

“Overview. Onions, garlic, and leeks are from a group of plants called alliums, which are all toxic to dogs and cats. Symptoms of onion and garlic poisoning include vomiting, diarrhoea and a reduced appetite.”

If your pet is struggling to breathe, has collapsed, is having a seizure or can't stand up: go to the nearest vet now.

Not sure how serious it is?

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Common questions

What signs can onion and garlic poisoning cause in dogs?

Signs can include vomiting, diarrhoea, a sore abdomen, reduced appetite and dehydration.[1]

How might a vet find out what is wrong?

A vet may carry out blood tests.[1]

When should I contact a vet?

Contact your vet as soon as possible if you think your dog has onion and garlic poisoning.[1]

Sources

  1. PDSA

How this page was made: written with the help of AI from the sources below, then checked claim by claim against those sources. Urgency levels follow OkPaw’s fixed safety rules. It is guidance, not a diagnosis. How we write our pages

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