Gastroenteritis and Gastritis

Gastroenteritis is an inflammation or infection of the stomach and intestines in general. Gastritis is an inflammation or infection confined to the stomach. These diseases can range from mild and self-correcting to severe and rapidly fatal. A chronic form exists that causes weight loss and general ill health.

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; improperly functioning internal organs; 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 gastritis and gastroenteritis are:

  • Vomiting
  • Diarrhea
  • Depression
  • Fever
  • Adominal pain
  • Decreased appetite and water intake
  • Weakness
  • Weight loss and other abnormalities


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

Diagnosis is based on clinical signs, examination findings, stool and blood tests and response to treatment. X-rays are sometimes necessary. A rectal exam or possible endoscopic imaging of the digestive system may be needed for persistent cases.

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 to 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 or 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 other pets. Use separate feeding, bedding and grooming items. Wash your hands after handling to reduce the chance of transmission.
  • If your pet has a serious contagious disease, the medical team may have additional recommendations to reduce any spread of the illness.

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