Diarrhea in Dogs: Causes and Treatment

ASPCA logoDiarrhea is characterized by frequent loose or liquid bowel movements. It can be caused by something as simple as a change in diet or a more serious illness or infection. Diarrhea may be sudden in onset and short in duration. It can also last for weeks to months or occur off and on. A single bout of diarrhea is generally not a cause for concern in dogs -- but if it persists for more than a day, it can lead to dehydration, or it may indicate an underlying health issue and should be checked out by a veterinarian.

What Causes Diarrhea in Dogs?

Change in diet
Food intolerance
Ingestion of garbage or spoiled food
Ingestion of poisonous substances or toxic plant material
Ingestion of foreign body (for example, toy, rubber band, plastic bag, etc.)
Allergic reaction
Bacterial or viral infection
Internal parasites, such as roundworms, coccidia and giardia
Inflammatory bowel disease
Kidney or liver disease
Cancer or other tumors of the digestive tract
Certain medications
Colitis
Stress
Hemmorhagic gastroenteritis

What Are the General Symptoms of Diarrhea?

Loose or liquid, frequent stools are the most common symptoms of diarrhea in dogs. Other signs include flatulence, blood or mucus in stool, changes in volume of stool and straining to defecate. Lethargy, dehydration, fever, vomiting, decreased appetite, weight loss and an increased urgency to defecate may also accompany diarrhea.

If your dog’s diarrhea is black, he could be experiencing internal bleeding of the stomach or small intestine and should be examined by a vet immediately.
How Do I Treat Diarrhea?

It is often recommended that you avoid giving your dog any food for 12-24 hours while he’s experiencing diarrhea, but do provide plenty of fresh, clean water to stave off dehydration. Check with your veterinarian about the proper course of treatment for your dog’s specific case.
When Should I Take My Dog to the Vet?

Bring your dog to the vet if his diarrhea continues for more than a day, or if you observe lethargy, vomiting, fever, dark-colored or bloody stools, straining to defecate, decreased appetite or unexplained weight loss. Contact your veterinarian immediately if you notice your puppy has diarrhea, as it can be an important indicator of serious diseases in young dogs.

What Can I Expect at the Vet’s Office?

Your veterinarian will examine your dog for underlying illnesses and assess for dehydration. He or she may take a stool sample to check for the presence of internal parasites, as well as conduct blood tests to identify a possible cause of the diarrhea.

Other diagnostic tests might include radiographs, ultrasound, cultures, endoscopy and biopsy. The diagnostic tests performed and treatment recommended will depend on how the long the diarrhea has been going on and the severity of your dog’s condition.

Are Certain Dogs Prone to Diarrhea?

There are certain breeds that may be predisposed to developing conditions that lead to diarrhea. German shepherds, for example, are known to have an increased prevalence of exocrine pancreatic insufficiency in the breed. Young dogs are more likely to have infectious and parasitic-related diarrhea than adult dogs.
How Can I Prevent Diarrhea?

Keep in mind that even perfectly healthy dogs will sometimes get diarrhea. Here are tips to reduce the likelihood of occurrence:

Keep up to date with your dog’s vaccinations.
Make sure your dog is free of parasites by following your veterinarian’s recommendations.
Don’t let your dog have access to garbage, spoiled food, etc.