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Can cats eat mustard?

Unsafe

Quick answer: No — mustard is not safe for cats and should never be given.

Quick verdict

Unsafe

Key risk

Mustard seeds cause stomach upset and the condiment is salty and spicy.

Why

Mustard is toxic to cats and must be avoided.

Can cats eat mustard, and why?

Mustard is toxic to cats and must be avoided. Mustard seeds cause stomach upset and the condiment is salty and spicy.

Cats are obligate carnivores: they must get most of their nutrition from meat and need nutrients such as taurine that only animal products provide. They lack some enzymes for processing plants and carbohydrates, so fruit and veg offer little benefit and can upset their stomach; many cats are also lactose intolerant.

Warning — what to watch for

Mustard seeds cause stomach upset and the condiment is salty and spicy.

If your cat has eaten mustard, don’t wait for symptoms — contact your vet immediately, or call the Animal PoisonLine on 01202 509000 (24/7, UK). Signs of a problem can include vomiting, diarrhoea, drooling, lethargy, tremors or loss of appetite.

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Frequently asked questions

Can cats eat mustard?

Unsafe. Mustard is toxic to cats and must be avoided.

What happens if my cat eats mustard?

Mustard seeds cause stomach upset and the condiment is salty and spicy. If your cat has eaten mustard, contact your vet or the Animal PoisonLine (01202 509000) straight away — don’t wait for symptoms.

Is mustard poisonous to cats?

Unsafe. Mustard is toxic to cats and must be avoided.

Free printable: safe & toxic foods for cats

mustard is just one food — get the full one-page checklist of what’s safe, fine in moderation, or dangerous for cats. Vet-sourced, yours to print and keep.

Check mustard for another pet

Sources

Our verdict on whether cats can eat mustard draws on established UK and US veterinary and welfare organisations. Individual pets, quantities and preparation vary — always confirm with your own vet.

General guidance based on established veterinary sources (ASPCA, PDSA, Blue Cross, RSPCA), not a substitute for advice from your vet. If you’re ever unsure, or your pet has eaten something harmful, contact your vet or the Animal PoisonLine on 01202 509000.