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Home > Dogs > Why Is My Dog’s Poop Watery? Vet-Reviewed Causes & Next Steps

Why Is My Dog’s Poop Watery? Vet-Reviewed Causes & Next Steps

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Dr. Nia Perkins

Veterinarian, DVM

The information is current and up-to-date in accordance with the latest veterinarian research.

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As gross as it seems, looking at your dog’s poop is an easy way to monitor their health. Poop can tell you whether your dog has certain types of worms, and you can look for changes in the color or texture of it to see if anything looks out of the ordinary.

If you are someone who monitors your dog’s poop, or you’ve had to clean up any unpleasant messes in your home, you may have noticed your dog’s poop being watery or runny. It’s very common for dogs to have watery poop occasionally, but if this is a regular occurrence, it could be a sign that something more serious is going on.

In this article, we’ll take a closer look at what can cause dog poop to be runny. We’ll also explain when it isn’t a cause for concern and when you should take your dog to the veterinarian. Continue reading to learn more.

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What Constitutes As Diarrhea?

If you’ve noticed that your dog’s poop is more watery than usual, then you’re likely already aware that your dog is suffering from diarrhea. Diarrhea is essentially when your dog’s poop is looser or runny, and it occurs in large amounts or more than just once or twice, sometimes over a few days.

For example, if your dog only has watery poop once a day, especially after eating, it likely isn’t diarrhea but rather a result of something in the food that just didn’t agree with your dog at the time. But if it’s diarrhea, it will occur more than once per day or more than just soon after eating.

It’s also worth noting that diarrhea isn’t a disease but a side effect of other diseases or illnesses. The disease or illness could be minor, and the diarrhea could resolve quickly with the help of a more bland diet. Or, it could result from a more serious or even life-threatening illness and require treatment from a veterinarian.

You must know the potential causes of diarrhea in dogs. This can help you determine the best course of action to take toward finding a treatment.

What Causes Diarrhea in Dogs?

Dog Diarrhea
Image By: A photographyy, Shutterstock

Unfortunately, there isn’t just one cause of diarrhea. If your dog is experiencing diarrhea, some of the potential causes may be more easily recognizable than others.

As you read through this list, consider whether your dog has undergone any dietary changes or a major life change. If you can attribute your dog’s diarrhea to either of those, it likely isn’t a major cause for concern. But it might be worth speaking with a vet if you can’t pinpoint an exact reason.

Below are the most common reasons why your dog may be experiencing diarrhea.

Dietary Changes

In many cases, diarrhea in dogs can be due to something as simple as a change in diet. For example, if you just switched to a different food with no transition period, they may experience stomach issues. Dog food contains different amounts of nutrients, and your dog’s stomach may not be able to quickly adjust to digesting the different levels. It may take days to weeks to make that adjustment.

If you have just switched to new dog food and your dog isn’t experiencing symptoms other than diarrhea, this is likely the cause, and it should resolve on its own within a few days. But when switching dog foods, it’s a good idea to do so slowly and incorporate some of the new food in with the old, then gradually phase out the old food until your dog is eating nothing but the new food. That way, his stomach will have time to adjust.

Stress/Lifestyle Changes

Dog Pooping
Image By: Pezibear, Pixabay

Another common cause of diarrhea in dogs is stress or a lifestyle change. Your dog may experience diarrhea due to being nervous or feelings of uncertainty.

Some of the lifestyle changes that could cause stress in your dog are:
  • Recent adoption
  • Being temporarily boarded
  • Separation anxiety
  • Introduction of a new pet or family member
  • Moving to a new home
  • Losing a loved one

If your dog’s diarrhea is caused by stress, it should resolve on its own within a few days with minor or no treatment once it adjusts to the new situation. But if it continues past that, or you notice they aren’t eating or seem depressed, this may be a sign that something more serious is going on, and you should see a vet.

Dietary Indiscretion/Garbage Toxicosis/Poisons

Dietary indiscretion and garbage toxicosis, sometimes called garbage gut, are terms used to describe that your dog ate something that he shouldn’t have. This may apply to food scraps or trash that was contaminated with bacteria. It can also include ingestion of a poisonous substance or plant.

In addition to diarrhea, garbage gut can lead to other signs, including vomiting, stomach pain, stomach growls, and flatulence. In mild cases, this illness will resolve on its own within a day or so and won’t require any treatment. But in more severe cases, it can result in problems such as pancreatitis, gastrointestinal obstruction, or seizures. These conditions will require immediate veterinary attention.

Your dog ingesting something poisonous, whether human food or a plant, can be serious and even deadly. If you suspect your dog ate something poisonous, get him to a veterinarian immediately or call the animal poison control hotline.

Food Intolerance/Allergies

Jack Russell Dog Guilty For The Poop
Image Credit: Kiadtisak-Khwanyu, Shutterstock

If your dog has diarrhea lasting more than a few days and occurs not long after he eats, it could be a sign of food intolerance or an allergy toward something in his food. This is especially true if it is accompanied by vomiting or frequent scratching, hair loss, coughing or sneezing, and even red skin.

Common food allergies in dogs include proteins, especially those from dairy products, beef, lamb, chicken, chicken eggs, soy, or gluten (from wheat). All of these can be found in dog foods. Dogs can also be allergic to other things, like fleas. If you suspect a food allergy is the cause of your dog’s diarrhea, it’s a good idea to take them to the vet to find out exactly what he or she is allergic to. A specific food type may be necessary to help prevent diarrhea.


Viruses, such as parvo and distemper, bacteria, such as salmonella, and parasites, such as hookworms, roundworms, and giardia, can all cause diarrhea in dogs. Some parasites, like tapeworms, are easily recognized. Tapeworm segments resemble rice and may be found in the poop. Bacteria and viruses are a little harder to pinpoint as the cause.

If you can’t attribute your dog’s diarrhea to another cause, a virus, bacteria, or parasite may be worth considering. A veterinarian can help diagnose these agents that may be affecting your dog.

Other Illnesses/Medication

If your dog is suffering from another illness or on medication, this may be a cause of diarrhea. If you know that your dog has an illness or is on medication, reach out to your vet if they are experiencing diarrhea.

When to See a Vet About Your Dog’s Diarrhea

vet. examining labrador dog
Image Credit: SeventyFour, Shutterstock

If you can’t determine a potential cause of your dog’s diarrhea, if other side effects accompany it, or if it doesn’t resolve within a couple of days, it’s a good idea to have them seen by a veterinarian. Your dog could have an undiagnosed illness or need specific treatment to make the diarrhea stop. Otherwise, it can leave your pooch dehydrated.

Your vet will likely run a series of tests to determine whether your dog’s watery poop is caused by an illness, bacteria, virus, parasite, or something else. Depending on what the tests show, medication or a special diet may be prescribed.


Final Thoughts

If your dog is experiencing watery poop or diarrhea, the prognosis is usually good. However, it’s important that you seek veterinary treatment if you can’t figure out the cause of the diarrhea, or if it’s accompanied by other signs. Even though diarrhea itself is usually not serious, what’s causing it could be, so it’s important that you seek help if you aren’t sure so that you can get your dog feeling better.

Featured Image Credit: SasaStock, Shutterstock

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