Can dogs eat walnuts? And cats?
Avoid. Moldy walnuts cause tremors and seizures; fresh ones are fatty and can block.
Avoid: fatty, choke-sized, and with the same mold risk.
Walnuts, especially black walnuts and any nut that has sat outside, can carry molds that produce tremorgenic mycotoxins: tremors and seizures in dogs. Even clean English walnuts are high-fat, choking-sized and gut-blocking. There is no version of a walnut worth sharing with a pet, so this one sits at avoid.
Signs to watch for
- Moldy: tremors, seizures
- Fresh: vomiting, stomach upset, blockage
Sources: ASPCA Animal Poison Control people-foods guidance, Merck Veterinary Manual, Pet Poison Helpline. Verdicts are conservative by design: where evidence is thin we choose the stricter rating.
This is general educational information, not veterinary advice. When in doubt about your own pet, ask your veterinarian.
If your pet just ate something risky, act now: call your vet, ASPCA Animal Poison Control at (888) 426-4435, or Pet Poison Helpline at (855) 764-7661 (consultation fees may apply).