Can Dogs Eat Mustard?

By Coty Perry

No, dogs cannot eat mustard. Mustard contains mustard seeds that have toxic compounds causing inflammation of the stomach and gastrointestinal system. Mustard is not safe for dogs.

Did your dog eat mustard and you’re afraid it’s dangerous? While consuming a small amount of mustard will likely not hurt your dog, consuming a large amount of mustard can have some health risks. If you wonder, “can dogs eat mustard?” We can help answer your question.

Is Mustard Bad for Dogs?

Yes, mustard is considered bad for dogs. Mustard seeds are toxic for your dog to ingest and can bring on some unwanted health risks. 

Health Risks of Eating Mustard for Dogs

There are a few health risks associated with dogs ingesting mustard. 


Gastroenteritis is when your dog’s stomach and intestinal tract become inflamed. It will most commonly display as diarrhea either with vomiting or without vomiting. However, it can also manifest as just vomiting. This condition can be chronic, lasting more than two weeks. 

It can also be acute, where it does not last long and will typically go away on its own. Some other symptoms of Gastroenteritis include stomach pain, gagging, dry heaving, loss of appetite, and lethargy. Your dog’s vet can prescribe medication to help treat this condition, and will sometimes recommend that you follow a bland diet.

If your dog’s symptoms of vomiting and diarrhea last longer than 24 hours, you should call the vet immediately. These symptoms can cause your dog to become severely dehydrated and your vet will be able to help your dog get some relief. Your dog’s vet might begin IV fluids for your dog to help them become hydrated and possibly might prescribe medication for your dog.

If you’re afraid to call your vet because of how much their services may cost then you should use Pet Assure to save as much as 25% on your Dog’s veterinary care.

Thyroid Damage

Ingesting mustard can lead to thyroid damage in your dog. Some common symptoms of hypothyroidism in your dog are exercise intolerance, weight gain, lethargy, obesity, hair thinning, hair loss, and increased shedding. Your dog might also experience mental dullness, cod intolerance, skin thickening, or reproductive disturbances if they are intact. 

If your dog develops hyperthyroidism, your dog might experience weight loss, increased appetite, increased thirst, frequent urination, vomiting, diarrhea, increased amount of stool, weight loss, and extreme excitement. Some more severe symptoms of hyperthyroidism include shortness of breath, enlarged heart, congestive heart failure, heart murmurs, or tachycardia.

What Is Mustard?

Mustard is a popular condiment that is usually used on things such as hamburgers, hot dogs, and much more. It can also be used to cook some dishes because it has a tangy flavor that a lot of people enjoy.

Mustard comes in many varieties, but the French mustard, or yellow mustard, is most commonly used. Yellow mustard typically contains the following ingredients:

  • Lemon juice
  • Horseradish
  • Wine
  • Turmeric
  • Flour
  • Paprika
  • Garlic powder
  • Mustard seeds
  • Spices
  • Flavorings
  • Salt
  • Other liquids

For dogs, some of these ingredients are known to cause issues. For example, garlic is considered toxic for dogs. Paprika and horseradish are also regarded as harmful. Most importantly, mustard contains mustard seeds and this can make your dog sick. 

Mustard seeds contain glucosinolates, which are toxic for your dog. Glucosinolates can cause vomiting, diarrhea, nausea, and other gastrointestinal issues. In addition, mustard seeds also affect your dog’s thyroid.

How Much Mustard Is Toxic to Dogs?

If your dog just licked a small amount of mustard off your plate, it will most likely be fine. However, if your dog consumes a large amount of mustard, then they could be in danger of developing some of the health risks discussed in this article. 

Can Eating Mustard Kill a Dog?

Mustard seeds have the potential to kill a dog, but only if the dog ingests extremely high amounts. It is unlikely that your dog will die from having mustard because they don’t typically have access to such a large amount. However, be sure to seek medical treatment for your dog right away if you believe they ingested too much mustard.

Can Dogs Eat Dijon Mustard?

Dijon mustard is not the same as French mustard, but it is still harmful to your dog. Dijon mustard is made from mustard seeds and contains white wine or wine vinegar. Since it contains mustard seeds, your dog should not have it. 

Can Dogs Eat Honey Mustard?

While honey can be soothing for dogs, honey mustard is unsafe. The combination of honey and mustard together is harmful to your dog and will most likely make them feel sick. If your dog has a small amount of honey mustard, they will be fine. If they eat a large amount, your dog can become very sick.

Can Dogs Eat Mustard Greens?

Dogs can eat mustard greens. They are safer for dogs to eat because they don’t contain any mustard seeds. That being said, you shouldn’t feed your dog raw mustard greens. The canine stomach wasn’t design to breakdown and digest raw veggies.

If you want to serve mustard greens to your dog, it’s best to steam them without spices.

Can Dogs Eat Mustard Powder?

It is not recommended for your dog to eat mustard powder, as this can induce vomiting.

What Should I Do If My Dog Ate Mustard? 

If your dog consumed some mustard, you should follow this treatment plan.

Monitor Your Dog

If you notice that your dog ingested a small amount of mustard, watch them closely to see if any symptoms develop. Your dog will most likely start vomiting to quickly remove toxins from its body.

Contact the Vet

If you think your dog consumed a lot of mustard, contact your dog’s vet as soon as possible.

What Will The Vet Do If My Dog Ate Mustard?

Here are some of the things a vet will do if your dog ate mustard.

IV Fluids

If your dog has been experiencing diarrhea or vomiting, it is likely that they are dehydrated. The vet will most likely give your dog IV fluids to hydrate them and flush out the harmful toxins quickly.


Your vet might consider inducing vomiting in your dog to prevent them from absorbing the harmful toxins.

Activated Charcoal

Activated charcoal is used after emesis to prevent your dog from taking in any remaining toxins from the mustard.

Recommend a Bland Diet

Your dog’s vet might recommend either withholding food for a few days to let their stomach settle or following a bland diet. A bland diet consists of plain food and lots of water to keep them hydrated.


Can dogs eat mustard? The answer is no, they should not eat mustard because of the many health risks it can cause. Mustard contains many harmful substances for your dog, like mustard seeds, paprika, and garlic powder. 

If you discover that your dog has eaten some mustard, there is no need to panic. Be on the lookout for signs of gastroenteritis or signs of thyroid damage. Monitor your dog closely and be sure to call the vet if you believe they consumed too much mustard.

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Coty Perry
Coty is a self-proclaimed cat whisperer and animal lover. Growing up his mom ran a dog training business out of his childhood home so you can say it was complete chaos 24/7. Today, when he comes home after a long day of writing about animals, he’s greeted by his two loving cats Marley and Cozmo.