First Walk is on Us!

✓ GPS tracked walks
✓ Activity reports
✓ On-demand walkers
Book FREE Walk

Jump to Section

What is Having Diarrhea?

Dogs can develop diarrhea for a number of reasons. Diarrhea can be mild, moderate or severe. Mild and moderate diarrhea can usually be resolved using over the counter anti-diarrhea medications that are recommended by your veterinarian. Severe diarrhea can cause your dog to quickly become dehydrated and a trip to see your veterinarian will be necessary. Once you are able to stop your dog’s diarrhea, then you will need to find out what caused the problem. 

Diarrhea in dogs can happen at any time and for many different reasons. Bloody, watery diarrhea is the most concerning in dogs and it could possibly be a sign that your dog has contracted the canine parvovirus. This is a highly contagious virus that dogs that are unvaccinated are susceptible. While diarrhea in dogs is messy and can be frustrating for the dog’s owner, it can also be a symptom of a bigger health problem. When your dog is suffering from diarrhea, speak with your veterinarian about the issue. Possible causes of your dog having diarrhea include:

  • Dietary changes and/or indiscretions
  • Infectious viruses
  • Gastrointestinal illnesses
  • Food intolerances
  • Intestinal parasites
  • Poisoning
  • Bacterial infection
  • Stress 
  • Reaction to medications

Book First Walk Free!

Why Having Diarrhea Occurs in Dogs

Dietary Changes

Dogs love to forage for food anywhere and they will eat almost anything. Dietary indiscretions, such as eating spoiled food or garbage or simply eating too much food can cause your dog to experience diarrhea. Depending on what they have eaten and how much will influence how severe their diarrhea becomes. A change in their diet can also cause them to develop diarrhea. It is important to not switch their food often to avoid stomach upset and diarrhea. 

Infectious Viruses

Infectious viruses such as parvovirus, coronavirus and distemper can cause your dog to have diarrhea. With parvovirus, your dog will develop bloody, watery diarrhea. Dogs that have contracted an infectious virus and have diarrhea are at extreme risk of quickly becoming dehydrated. Bacterial infections can also cause your dog to have diarrhea. 

Gastrointestinal Illnesses

Illnesses that affect the gastrointestinal tract such as liver or kidney disease, cancer, colitis or inflammatory bowel disease can also cause bouts of diarrhea. With many of these illnesses, the diarrhea becomes chronic and will require prescription medication to help stop it. 

Intestinal Parasites

Intestinal parasites, especially in puppies, can cause mild to severe diarrhea. Intestinal parasites include giardia, coccidia, hookworms, roundworms and whipworms. A simple fecal examination will diagnose intestinal parasites. Your veterinarian will prescribe a de-worming medication that will eradicate the intestinal parasites and alleviate your dog’s diarrhea.


Dogs that are experiencing stress can also develop diarrhea. Once your veterinarian has examined your dog and found no possible medical cause for your dog’s diarrhea, it is time to look at environmental factors that could be causing stress on your dog. Stress from separation anxiety or storms can cause your dog to have bouts of diarrhea. 


Certain medications can also cause your dog to experience diarrhea. Look at your dog’s medications and research the side effects. Ask your veterinarian about the medications your dog is on and if diarrhea could be a possible side effect.

What to do if your Dog is Having Diarrhea

Sometimes it can be difficult to determine the right time to call your veterinarian. Some dogs are simply prone to digestive upset including diarrhea and their owners may not feel that mild to moderate diarrhea needs to be checked by their veterinarian. There are some things to watch for when your dog has diarrhea that will let you know that you should make an appointment with your veterinarian and have your dog checked over.

  • There are other physical symptoms present such as vomiting, weakness, lethargy, fever or pale gums
  • The diarrhea does not stop or has been ongoing for several days
  • Your dog is showing symptoms of dehydration
  • Your dog is currently taking medications for another condition

Once you make the decision to take your dog in to see their veterinarian, your veterinarian will then begin their assessment and determine what is causing the diarrhea. Generally, a stool sample will be collected and a fecal exam done to look for any intestinal parasites. If no parasites are found, your veterinarian will begin looking for other causes. Stopping the diarrhea will be paramount for your veterinarian while they are looking for the cause.

Prevention of Having Diarrhea

Vaccinations are very important to keep your dog from contracting an infectious virus. Speak with your veterinarian about your dog’s vaccination schedule and be sure to have vaccines given on time to keep your dog protected. Regular de-wormings are also a good preventative to ensure that your dog does not become infected with intestinal parasites.

Avoid changing your dog’s diet or giving them too many treats. This can cause gastrointestinal upset and diarrhea. Research your dog’s food and the quality of ingredients to ensure that they are getting all the nutrients that they need without adding fillers that can cause diarrhea.

Cost of Having Diarrhea

Many times, diarrhea will resolve with simple home remedies or over the counter medicines. However, when you have to visit your veterinarian because of your dog’s diarrhea, the cost can vary depending on the diagnosis. Intestinal parasites can cost from $200 to $500 to treat, whereas parvovirus can cost around $5500 to treat.