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What Causes Diarrhea in Dogs — and How to Stop It

December 27th, 2017 by Cherished Companions Animal Clinic

Carrie holds her dog, Piper, who has been suffering from dog diarrhea.

“Help, my dog has runny poop!”

If your dog’s poop is runny, take heart, just about every dog gets diarrhea from time to time. You’re smart to look into answers.

First, the good news: Our Castle Rock veterinarians can help you stop many types of dog diarrhea quickly.

The bad news is: There are some types of diarrhea in dogs that can be tougher to stop and keep from coming back (such as runny poop caused by intestinal parasites).

The important thing is to identify what’s causing your dog’s diarrhea.

That way, you’ll know how to address it and how to help your dog feel better quickly.

What causes dogs to get diarrhea?

Your dog’s body is trying to get rid of an irritant somewhere in his or her intestinal tract.

The most common causes of runny poop in dogs are:

  • Intestinal parasites (like giardia or roundworms)
  • Sudden food changes, such as changing to a new kibble (tip: it’s better to slowly mix the foods together over a week than to make a sudden change)
  • Nibbling on things in the yard (such as plant material)
  • Eating foods they aren’t used to (such as steak, table scraps or garbage)
  • Stress

If your dog is experiencing recurring (chronic) diarrhea, there could be other issues at play, such as:

  • Food allergies
  • Gastrointestinal lymphoma
  • Irritable bowel syndrome

What should you do if your dog has diarrhea?

It depends on what’s causing your dog’s diarrhea.

To figure out what you need to do for your pup, bring your dog’s most recent stool sample into our veterinary clinic.

(You can bring it in at any time. There’s no appointment needed.)

Our veterinarians will run a fecal test to determine the cause of the diarrhea. We’ll let you know:

  • Whether you need to bring your dog in
  • The steps you need to take for your dog’s situation
  • The prescription that may be needed (if any)

Tips to help you collect a fecal sample from your dog

We know this isn’t the fun part of being a pet parent! But bear with us, here are a few tips to be more successful:

  • Make sure you collect enough stool. You want a sample that’s roughly the size of a grape or a tablespoon. (You’re welcome to stop by our clinic to get a complimentary fecal cup and scoop to make the collection process easier.)
  • Make sure the fecal sample is as fresh as possible — no more than 5 to 8 hours old.
  • Keep the sample in a cool area or the refrigerator if you can’t get into our clinic that fast. Important tip: Do not freeze the stool or allow it to dry out.

Is there anything else you should be doing for your dog?

Make sure your dog keeps drinking water. While diarrhea is not as dehydrating as vomiting in dogs, it still can happen.

You also may want to feed your dog a bland diet — such as a 3:1 mix of cooked white rice and boiled hamburger or boiled chicken.

(Portion size varies by dog.)

If your dog has chronic diarrhea and you aren’t able to cook up a bland diet, we have prescription diets you can give your dog that contain the needed nutrients without the irritation.

For the day or two after the diarrhea clears up, your dog may not have to poop.

This is normal and hopefully, a welcome surprise!

Does your dog have a more serious issue than just diarrhea?

 Call the vet right away if your dog also:

  • Is vomiting
  • Isn’t eating
  • Isn’t drinking
  • Isn’t acting like he or she typically does
  • Is passing large amounts of blood in his or her diarrhea (a small amount of blood is normal)

It’s important to make sure your dog isn’t experiencing a more serious health issue. 

 Help your dog feel better today

If you live in Castle Rock or the Denver area, call our veterinarians at 303-688-3757 or:

Book your visit here 


Cherished Companions Animal Clinic is a veterinary clinic in Castle Rock, Colorado. Specializing in the care of cats and dogs, our goal is to help you and your pet feel more comfortable, keeping your stress to a minimum.

This article is intended to provide general guidance on diarrhea in dogs. If you have specific questions or concerns, please contact your local veterinarian. (If you live in or around Castle Rock, we welcome your call.)

© 2017, Cherished Companions Animal Clinic

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