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Tailwise

Vegetable

Can cats eat onions?

No Toxic

Cats are even more sensitive to onion than dogs; a small amount of onion powder in baby food or soup has caused anaemia.

Why N-propyl disulphide and related sulphur compounds

Photo: USDAgov (public domain) via flickr

If your cat ate some

  1. Call your vet or a pet poison helpline straight away, even if your pet seems fine.
  2. Tell them what was eaten, roughly how much, when, and your pet’s weight.
  3. Do not try to make your pet sick unless a vet tells you to.
  4. Signs of anaemia can take several days to appear, so keep watching after a vet visit.

Signs to watch for

  • Weakness and tiredness
  • Pale or yellowish gums
  • Fast breathing and heart rate
  • Red or brown urine
  • Vomiting and diarrhoea

Dogs and cats, side by side

Dogs Toxic

No. Onions in any form — raw, cooked, powdered or in gravy — damage red blood cells and can cause anaemia. Effects build up if small amounts are eaten often.

Can dogs eat onions?

Cats Toxic

No. Cats are even more sensitive to onion than dogs; a small amount of onion powder in baby food or soup has caused anaemia.

The details

All members of the allium family — onions, garlic, leeks, shallots and chives — contain compounds that damage the red blood cells of dogs and cats. The cells burst, leaving the body short of oxygen-carrying capacity. Around 5 grams of onion per kilogram of body weight can cause changes in cats, and 15–30 g/kg in dogs.

Cooking does not make onion safe. Check labels on stock, soup, gravy, baby food and ready meals before sharing leftovers.

Safer treats your cat can have instead

Questions owners ask

Can cats eat onions?

No. Cats are even more sensitive to onion than dogs; a small amount of onion powder in baby food or soup has caused anaemia.

What makes onions risky for cats?

N-propyl disulphide and related sulphur compounds.

What are the signs to watch for in cats?

weakness and tiredness, pale or yellowish gums, fast breathing and heart rate, red or brown urine, vomiting and diarrhoea.

What should I do if my cat ate onions?

Call your vet or a pet poison helpline straight away, even if your pet seems fine. Tell them what was eaten, roughly how much, when, and your pet’s weight. Do not try to make your pet sick unless a vet tells you to. Signs of anaemia can take several days to appear, so keep watching after a vet visit.

Is onions safe for dogs too?

No. Onions in any form — raw, cooked, powdered or in gravy — damage red blood cells and can cause anaemia. Effects build up if small amounts are eaten often.

Sources

  1. ASPCA Animal Poison Control: people foods to avoid
  2. Merck Veterinary Manual: food hazards
  3. WSAVA Global Nutrition Guidelines

Tailwise is for general information and is reviewed by veterinary professionals, but it is not a substitute for advice from your own vet, who knows your pet. How we check facts

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