What to do if your pet ate it
Contact your vet or a poison line right away, report how much Walnuts was eaten and your pet's weight, and keep any packaging or leftovers. Do not induce vomiting unless your vet tells you to.
Signs to watch for
- Vomiting and diarrhoea
- Lethargy and weakness
- Loss of appetite
- Severe: tremors, breathing trouble, collapse
If your pet shows vomiting, lethargy or any unusual behaviour after eating Walnuts, go to the nearest emergency vet immediately.
Dogs and cats carry the same rating (Do not feed), so the notes below hold for either pet.
Other foods that are toxic or dangerous
The full A–Z food list groups every food by verdict for each species.
Why these cautions matter
Mouldy food can carry tremorgenic mycotoxins, which produce uncontrollable tremors and seizures rather than a simple stomach upset.
Frequently asked questions
Can cats eat Walnuts?
NO — do not feed. Risk of mould tremorgenic toxins and blockage; the shell can splinter. Avoid entirely.
What if my cat already ate Walnuts?
Call your vet or a poison line now with the amount of Walnuts eaten and your cat's weight, and do not induce vomiting unless a vet tells you to. If Walnuts was eaten and you then see vomiting, lethargy, tremors or breathing changes, go straight to the nearest emergency clinic.
Is there a safe amount of Walnuts for cats?
There is no accepted safe dose of Walnuts for cats; it is classed as toxic or dangerous, and reactions vary with the individual animal, so it is not something to feed at any amount.
How often can cats have Walnuts?
Walnuts is not something to feed at any interval; it stays off the menu entirely.
What are safer treats than Walnuts for cats?
Pick from the safe list instead — Collard greens or Sweetcorn kernels carry none of the risk that Walnuts does, and they work better as an everyday treat.