Common Causes (and Remedies) of Diarrhea in Pets


PetMD Editorial

Published Jul. 15, 2013
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Diarrhea Dilemma

By Cheryl Lock

While diarrhea is a prevalent ailment in pets, it’s not a problem that should be taken lightly. In fact, diarrhea can often be a clinical sign of many different underlying conditions for animals. We’ll take you through some of the common causes of pet diarrhea, the best ways to treat the illness when it hits your own pet, as well as some ways to prevent it in the future.

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Common Causes of Diarrhea in Dogs and Cats

Diarrhea is so common in pets that it’s actually been the No. 1 most claimed condition at Petplan for the last three years, says Dr. Jules Benson, VP of Veterinary Services at Petplan pet insurance. “It could be brought on by anything from a virus or parasites to poisoning, allergic reaction, autoimmune disease, or even certain types of cancer,” says Dr. Benson. The most common cause, however, usually occurs when an animal has eaten something that doesn’t agree with his system. “Diarrhea can also be a common side effect of some pet medications, including antibiotics, non-steroidal anti-inflammatory drugs and heart medications,” says Dr. Benson. “Further complicating matters, some pets also experience diarrhea as a result of excitement or stress.”

The Best Treatment of Diarrhea in Pets

Of course treatment for diarrhea will vary based on what’s causing it. “If the diarrhea is being caused by an underlying condition, the vet will work to control that, while advocating treatment that will alleviate your pet’s symptoms,” says Dr. Benson.


If you believe the cause of your pet’s diarrhea to simply be a general upset stomach, the most common recommendation is to switch to a bland, digestible diet (either a prescription diet from your veterinarian or a home-made recipe like plain white rice and boiled chicken) until the diarrhea abates, says Dr. Benson. As the symptoms subside, you can then gradually switch back to regular food.


Your vet may also prescribe medications to help alleviate nausea, excess gastric acid production or gastrointestinal inflammation.

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How to Avoid a Stinky Situation

There are a number of ways that you can help your pet avoid getting diarrhea in the first place, but again, a lot of what you do will depend on where you believe the issue is coming from. “If your pet got into the waste bin and developed a case of the runs, you probably just need to think twice about keeping trash out of paw’s reach,” says Dr. Benson. “But if your pet is easily upset by changes to his routine, or you’ve recently switched his food, then you could consider making slower transitions, or reconsider them altogether.”


If the problem appears to be medicine related, talk to your vet about possible alternatives that might be easier on your furry friend’s stomach, suggests Dr. Benson. “If you find yourself dealing with this problem frequently, talk to your vet about looking deeper into the issue.”

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When to go to the Vet

Diarrhea that has lasted for more than 24 hours could indicate something more serious than a simple stomach bug, and if left unchecked it can quickly lead to dehydration. “However, if your pet’s stool is bloody, dark or tarry, if he seems lethargic or has lost his appetite, or is also vomiting, don’t wait 24 hours,” says Dr. Benson. “In those cases, you should get to the vet as soon as possible.”