Enteritis and Colitis

Enteritis is an inflammation or infection of the intestines in general. Colitis is an inflammation or infection confined to the large bowel. These diseases can range from mild and self-correcting to severe and rapidly fatal. A chronic form that persists over time, causing weight loss and general ill health, exists as well. Enteritis may be accompanied by "gastritis" (stomach inflammation or infection).

There are numerous causes, including ingestion of garbage, table food, toxins, irritants or foreign objects, diet changes, bacterial, viral and parasitic infections, allergies, abnormal bowel function, cancer and immune system disease.

Common infectious diseases and parasites include Parvo and Corona virus, salmon disease (in the Pacific Northwest), several types of worms and microscopic organisms such as Giardia and coccidia.

The symptoms of enteritis and colitis are:

  • Diarrhea
  • Abnormal stool
  • Vomiting
  • Depression
  • Fever
  • Abdominal pain
  • Decreased appetite
  • Decreased water intake
  • Weakness
  • Weight loss


Severe and/or bloody diarrhea can easily lead to fatal dehydration, blood loss and intestinal damage. Damaged intestines can leak deadly bacteria or their toxins into the body. This form of the disease requires immediate and thorough treatment.

Diagnosis is based on symptoms, examination findings, stool and blood tests and response to treatment that is prescribed by a veterinarian. X-rays are sometimes necessary. A rectal exam or possible endoscopic imaging may be needed for persistent colitis.

Treatment depends on the type, severity and duration of the disease. Antibiotics, dewormers, intestinal medications, fluid and electrolyte therapy and dietary modification are needed, as appropriate for the problem. Good nursing care is essential to a speedy recovery.

Important Points

  • Use all medications as prescribed by your veterinarian.
  • Monitor your pet's progress carefully and have him/her rechecked as recommended by your veterinarian.
  • If a special diet has been prescribed for your pet, please do not offer any other food, treats or table foods. It is important to follow the feeding instructions as outlined by your veterinarian.
  • Ensure that your pet has access to fresh water at all times.
  • Separate any ill pets from others and use separate feeding, bedding, and grooming items. Wash your hands after handling,and clean up stools immediately to reduce the chance of transmission, if your pet has a communicable disease.


If you have questions about this or any medical topic, please contact your Banfield hospital today.