Can dogs eat mustard?
Not recommendedNo, mustard is not worth feeding to a dog: mustard seed can irritate the gut, products are salty, and some recipes contain onion or garlic.
Reviewed by the Webvet Veterinarian Team · Last reviewed June 26, 2026
Why
Crushed and wetted mustard seed releases isothiocyanates that can irritate the gastrointestinal tract. Product recipes vary: many plain yellow mustards do not contain onion or garlic, while some deli and specialty mustards do. Sugar-free does not mean xylitol, so check the exact ingredient list and treat xylitol or birch sugar in a dog product as an emergency.
Risks to watch for
- Mustard seeds commonly cause vomiting, diarrhea, and abdominal pain
- Onion or garlic powder in some recipes is toxic and damages red blood cells
- High sodium causes excessive thirst and, in quantity, salt toxicity
- If the label lists xylitol or birch sugar, it is life threatening to dogs
What to do if your dog ate mustard
Check the exact product label and contact your vet or Pet Poison Helpline (855-764-7661) with the product, estimated amount and time, your dog's weight and history, and any symptoms. Xylitol or birch sugar on the label requires an immediate call.
Mustard nutrition
- Calories
- ≈60 kcal / 100g in one representative USDA entry
- Sodium
- ≈1100mg / 100g in one representative USDA entry
- Key nutrients
- Nothing meaningful for pets
Safe alternatives
More pantry & other for dogs
Frequently asked questions
Can dogs eat mustard?
No, mustard is not worth feeding to a dog: mustard seed can irritate the gut, products are salty, and some recipes contain onion or garlic.
What happens if a dog eats mustard?
Crushed and wetted mustard seed releases isothiocyanates that can irritate the gastrointestinal tract. Product recipes vary: many plain yellow mustards do not contain onion or garlic, while some deli and specialty mustards do. Sugar-free does not mean xylitol, so check the exact ingredient list and treat xylitol or birch sugar in a dog product as an emergency. Watch for: Mustard seeds commonly cause vomiting, diarrhea, and abdominal pain; Onion or garlic powder in some recipes is toxic and damages red blood cells; High sodium causes excessive thirst and, in quantity, salt toxicity; If the label lists xylitol or birch sugar, it is life threatening to dogs.
What should I do if my dog ate mustard?
Check the exact product label and contact your vet or Pet Poison Helpline (855-764-7661) with the product, estimated amount and time, your dog's weight and history, and any symptoms. Xylitol or birch sugar on the label requires an immediate call.
Sources
Reviewed by the Webvet Veterinarian Team
General guidance based on credible veterinary sources — not a diagnosis or a substitute for your veterinarian. If your pet ate something toxic or is unwell, contact your vet or a pet poison line right away.