Can Cats Eat Mustard?
By Pettings · Sources checked Nov 2, 2026
No. Keep mustard away from cats. We did not find a veterinary source that describes mustard poisoning in cats, so this is not about a known toxin. Mustard is a sharp, salty, acidic condiment with nothing a cat needs, and the flavored kinds can carry garlic, onion, sugar or alcohol.
Why Mustard Is a Problem for Cats
The Cornell Feline Health Center describes cats as obligate carnivores that rely on nutrients found only in animal products. Mustard is made from ground mustard seed mixed with vinegar, water and salt, and often turmeric for color. The seeds contain compounds that make mustard hot when they mix with liquid. That bite can irritate a cat's mouth and stomach, and most cats back away after one sniff.
Salt is a steady part of prepared mustard. The ASPCA lists salt among foods to keep away from pets because large amounts cause excessive thirst and urination and can lead to sodium poisoning. Specialty mustards add more. Honey mustard adds sugar or honey, and many honey mustard dressings add mayonnaise. Dijon is often made with white wine. Spicy brown, beer mustard and deli mustard blends may list garlic, onion or "spices." The Merck Veterinary Manual says cats are the species most sensitive to garlic and onion, and that powdered forms are the most common cause of poisoning in cats.
Mustard usually comes on hot dogs, pretzels, deli meat or sandwiches. Those foods are salty and fatty in their own right, and the World Small Animal Veterinary Association (WSAVA) notes that common human foods can exceed a cat's daily treat calories in one serving.
Signs to Watch For
A lick of yellow mustard may make a cat drool, shake its head or paw at its mouth. Larger amounts can lead to vomiting or diarrhea. If the mustard was salty and your cat ate a lot, the ASPCA lists vomiting, diarrhea, depression, tremors and seizures for too much salt. For mustard with garlic or onion, the Merck Veterinary Manual describes weakness, fast breathing, yellow gums and dark urine a few days later.
What to Do If Your Cat Ate Mustard
Call your veterinarian or the ASPCA Animal Poison Control Center at (888) 426-4435 right away if your cat ate more than a lick or got into a flavored mustard. Do not try to make your cat vomit unless a veterinarian tells you to. Bring the jar so the vet can read the label for garlic, onion, alcohol and sodium. Offer fresh water.
If your cat has a medical condition or eats a special diet, ask your veterinarian before sharing any condiment.
Common Questions
Is mustard toxic to cats?
We found no veterinary source that lists mustard as poisonous to cats. It still has no place in a cat's diet. Prepared mustard is sharp, salty and acidic, and flavored types can contain garlic, onion, sugar or wine. The ASPCA lists salt among foods to keep from pets, and the Merck Veterinary Manual warns that cats are highly sensitive to garlic and onion.
Can cats eat honey mustard?
No. Honey mustard adds honey or sugar to mustard, and dressing versions often add mayonnaise and garlic. Cats have no need for sugar. The fat and garlic are bigger problems, since the Merck Veterinary Manual says cats are the species most sensitive to garlic. Keep honey mustard and chicken nuggets dipped in it away from your cat.
What happens if my cat licks mustard?
Most cats that lick mustard react to the sharp taste by drooling, shaking their head or pawing at their mouth, then walk away. A small lick usually causes no more than that. If your cat ate a larger amount, vomiting or diarrhea may follow. Call your veterinarian if signs last, or if the mustard contained garlic or onion.
Can cats eat hot dogs with mustard?
No. Hot dogs are salty, fatty processed meat, often seasoned with garlic and onion, and mustard adds more salt. The ASPCA lists salty foods among those to keep away from pets, and the World Small Animal Veterinary Association notes that human foods can exceed a cat's daily treat calories in one serving. Plain cooked chicken is a better choice.
Can cats eat mustard greens?
Mustard greens are the leaves of the mustard plant, not the condiment. Cats have no need for leafy greens, since the Cornell Feline Health Center describes them as obligate carnivores that rely on nutrients found in animal products. If you cook greens with garlic, onion, bacon or salt, keep them away from your cat, and ask your veterinarian before offering plain greens.