Are Black Walnuts Toxic to Pets?
Yes — black walnuts are toxic to cats. Yes — black walnuts are toxic to dogs. Yes — black walnuts 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
- Juglans nigra
- Toxic compound
- Tremorgenic mycotoxins (in moldy nuts); juglone
- Toxic parts
- Moldy nuts and hulls; wood shavings for horses
- Also known as
- walnut, walnuts
Symptoms
Cats (toxic)
- Vomiting
- Diarrhea
- Drooling
- Reduced appetite
Dogs (toxic)
- Vomiting
- Diarrhea
- Drooling
- Reduced appetite
Horses (toxic)
- Vomiting
- Diarrhea
- Drooling
- Reduced appetite
What to do
If your cat ate black walnuts
- 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 black walnuts
- 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 black walnuts
- 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
Moldy walnuts can cause tremors and seizures in dogs. Black walnut shavings in bedding can cause laminitis in horses.
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Frequently asked questions
Are black walnuts toxic to cats?
Yes — black walnuts are toxic to cats. Common signs include vomiting, diarrhea, drooling.
Are black walnuts toxic to dogs?
Yes — black walnuts are toxic to dogs. Common signs include vomiting, diarrhea, drooling.
Are black walnuts toxic to horses?
Yes — black walnuts are toxic to horses. Common signs include vomiting, diarrhea, drooling.
Which parts of black walnuts are toxic?
Moldy nuts and hulls; wood shavings for horses.
What makes black walnuts toxic?
Tremorgenic mycotoxins (in moldy nuts); juglone.