Cancer can cause diarrhea in a puppy, but so can eight other conditions, says a veterinarian.

Diarrhea in a puppy should never be ignored.

“Diarrhea is a very a common clinical sign of many conditions” in a puppy, says Dr. Jules Benson, BVSc, and VP of Veterinary Services at Petplan pet insurance.

“It’s so common, in fact, that non-specific gastrointestinal disease (i.e., conditions that cause the clinical signs of vomiting and/or diarrhea), is Petplan’s No. 1 most claimed-for condition for the last three years.”

Some Causes of  Puppy Diarrhea

“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.

“Puppy diarrhea is very common in newly adopted puppies and is most commonly due to dietary changes, stress of moving or intestinal parasites.”

Be on the Lookout for Additional Symptoms

“However, if your puppy is experiencing diarrhea combined with vomiting, lethargy and lack of appetite, it could be a more serious viral infection, such as parvovirus or canine coronavirus. So bring your puppy to the veterinarian at the first sign of an upset stomach.”

In summary, here are the nine possible causes of diarrhea in a puppy (no particular order):

– Non-specific G.I. disease

-Viral infection



-Allergic reaction

-Autoimmune disease


-Dietary changes

-Stress of moving

Dr. Benson is regularly consulted by many media outlets including ABC, NBC, FOX, The Wall Street Journal and The New York Times to provide pet health advice to pet parents nationwide. puppy diarrhea cancer
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.  


Top image: Shutterstock/Sonsedska Yuliia