What to Do When Your Pet Has Diarrhea

At the Worth Street Veterinary Center, we see pets with acute diarrhea—or what’s often referred to as gastroenteritis—on an almost daily basis. But what, really, is “acute diarrhea”? This is when your dog’s poop is soft, pudding-like (gross, right?), watery brown, or even slightly bloody. The most common cause is some sort of simple dietary indiscretion—say, your dog rifled through the garbage can, or you mistakenly changed his diet without slowly integrating in new food.

However, other causes are also possible. In puppies, diarrhea is often caused by intestinal parasites. In dogs of all ages, other causes include bacterial overgrowth, metabolic or inflammatory diseases, toxins, or viral/infectious diseases, especially in unvaccinated pets. In addition, medications such as antibiotics, steroids, or a non-steroidal anti-inflammatory (NSAID) may also cause GI upset. In short, there are a whole bunch of different reasons why your pet may have diarrhea.

Mild diarrhea (which is short in duration) may resolve by fasting your pet for 12 to 24 hours, then following up that period with a bland diet such as boiled rice and chicken or a prescription diet. Diarrhea that progresses longer than 1-2 days, or diarrhea accompanied with vomiting, usually requires a visit to your veterinarian. It can quickly lead to dehydration and electrolyte imbalances in young and senior patients.

A veterinarian will perform a physical exam and may recommend a blood chemistry profile, complete blood count, electrolyte panel and a urinalysis to rule out other causes of disease. In addition, always plan to take a fecal sample to your appointment to test for intestinal parasites and possibly a giardia antibody test (also known as an Elisa test), an intestinal parasite difficult to detect on a fecal float. An abdominal x-ray may be suggested to rule out whether a foreign body is causing irritation to the gastrointestinal system.

After assessing your pet, we may administer subcutaneous fluids (fluids underneath the skin) to maintain hydration, and we may prescribe an antibiotic and probiotics. If your pet appears dehydrated or if there is excessive diarrhea which may lead to dehydration or blood in the stool, he or she may require hospitalization and intravenous fluids.

Still have questions? Here’s a breakdown of some general rules to follow:

• Do NOT administer any type of medications (prescription or over the counter) without speaking to your veterinarian first.


• Do not abruptly change your pet’s food unless it is to a bland diet.


• Do not feed your pet if the diarrhea is accompanied by vomiting. Offer a bland diet if no vomiting is involved. It is best to offer multiple small meals (4-5 meals) daily.


• Do not wait to seek treatment if you have a very young puppy as he or she is prone to developing hypoglycemia (low blood sugar) with diarrhea and /or vomiting.


• Avoid administration of Imodium or any other antidiarrheal drug. These drugs can potentially worsen conditions, especially if there was any toxin ingestion.


• Never give a dog real bones. These can cause gastrointestinal upset or obstructions, and they may splinter off in the gastrointestinal system.


• Avoid giving your pet fatty foods, as these are not easily digestible and may lead to an inflammatory condition of the pancreas called pancreatitis.


• Call your veterinarian or make an appointment if your pet’s symptoms last over 24 hours and /or if they are accompanied by vomiting.


• Always offer water. A pet should have access to water at all times, 24 hours a day. The water should only be removed if your pet is vomiting or if your veterinarian recommends it.

Chronic or waxing and waning diarrhea may be a result of a more severe disease process and require additional diagnostics, including an abdominal ultrasound and /or endoscopy with biopsies. Please feel free to call us at the Worth Street Veterinary Center at 212-257-6900 with any questions or concerns regarding your pet. We look forward to speaking with you.

Julie Horton, DVM