The gastrointestinal tract in dogs has numerous normal bacteria that provide assistance with the digestion of food. In some cases the bacterium Clostridium perfringens multiplies and can cause acute (short term) or chronic (long term) diarrhea. The ingestion of uncooked meats, marine debris, and decaying vegetation may be the cause. Often this bacterium is introduced at dog parks or during kenneling of your dog. Dogs with a compromised immune system may have more trouble fighting the bacterial infection of Clostridium. Very young and older dogs are more likely to be compromised immune systems.  If your dog shows signs of diarrhea for more then one to two days a visit to your veterinarian is highly suggested.

Clinical Signs:

Abdominal stinting (hunched stance with painful abdomen), diarrhea that can appear darkened due to small amounts of blood, shiny mucous in diarrhea, tenesmus (straining to defecate), large volumes of watery diarrhea, lethargy (listlessness), occasionally vomiting, fever, collapse.


A veterinary examination will include a complete history and a complete physical evaluation. If your dog has been recently kenneled or visited dog parks it should be noted. Submission of a fecal sample to the laboratory is very helpful in diagnosing Clostridium infection. This bacterium is rod shaped and is easily viewed microscopically.  A blood sample may be evaluated for cell counts and organ function. In chronic cases the blood sample will help rule out systemic (throughout the body) infection.  In chronic cases an endoscope examination may be suggested to evaluate for intestinal problems. Intestinal endoscopy consists of passing a scope via the mouth and passed through the stomach to evaluate the small intestine. At this time the lining of the gastrointestinal tract is evaluated for inflammation and a biopsy (small sample of the cell lining is submitted to a laboratory) may be indicated.


Your dog may be treated on an outpatient basis. The treatment will include 2-3 weeks of oral antibiotics (amoxicillin, metronidazole, erythromycin, etc.) to fight the infection. Studies indicate that tetracyclin antibiotic is no longer effective as the bacterium has become resistant to it.  It is very important to finish the entire prescription. In conjunction your veterinarian may suggest over the counter medications to help resolve any intestinal inflammation. If your dog has become dehydrated (fluid loss due to diarrhea) it may be necessary to place an indwelling intravenous catheter (temporary catheter that provides access to a vein) to provide fluid therapy. In this case a day of hospitalization may be necessary. Other supportive therapy may include nutritional supplements to balance and promote normal intestinal bacteria. Probiotics such as lactobacillus can be added to your dog’s food.

Some veterinarians may suggest changing your dog’s food to a high fiber diet to help promote normal intestinal flora. Prevention involves avoiding the ingestion of decayed meats and vegetation. If your dog breaks with diarrhea it is  important to seek veterinary care soon to prevent dehydration and eventual collapse.

Clinical Terms:

Acute, chronic, compromised immune system, abdominal stinting, tenesmus, lethargy, systemic, endoscopy, biopsy, dehydrated, intravenous catheter, antibiotics, probiotics, high fiber diet.