Chronic vomiting and diarrhea in the dog can be a frustrating problem to treat. Successful treatment depends on an attempt to rule out all possible causes. Causes may include:

Food Allergy. Dogs may all of a sudden develop an allergy to some protein in the particular food being fed. There may be no explainable reason for this occurrence. Diagnosis is based on a food allergy trial utilizing sources of nutrients that have not been fed to the particular pet. A confirmed diagnosis can take several months.

Foreign Bodies. In some pets a foreign body, such as a small ball or marble may cause chronic vomiting and/or diarrhea if it does not cause a complete obstruction. Diagnosis is often confirmed by radiographs (X-rays).

Internal Parasites must be ruled out by internal parasite testing.

Chronic Pancreatitis may decrease the ability to digest foods properly resulting in diarrhea.

Chronic Liver or Kidney Disease may cause sporadic vomiting. Blood chemistry analysis is useful in confirming these diagnoses.

Inflammatory Bowel Disease:
This condition is thought to be an allergic reaction to some chronic irritation. The condition may affect the stomach and/or the intestine. Vomiting and/or diarrhea are dependent on the location of the lesions within the gastrointestinal tract. If only the stomach is involved, vomiting is usually the only sign. If only the colon is affected, then diarrhea is often the only sign observed. Diagnosis is usually confirmed with a biopsy and histopathologic examination of the tissue under the microscope. A diagnosis of IBD does not diagnose the underlying disease causing the problem. Sometimes it is possible to determine the exact cause, but in most cases it is never pinpointed. These cases are termed “idiopathic IBD.” Idiopathic IBD is usually treated with corticosteroids. Goals of treatment are to use the minimal dose possible to alleviate the clinical signs. It is usually necessary to initiate therapy with high doses, which can then be tapered off over a period of time.

Prednisone is the most commonly used corticosteroid. Prednisone remains in the body for approximately 36 hours after ingestion by mouth. Cortisone is normally produced by the adrenal gland. When the body is supplemented with additional corticosteroids, the adrenal glands stop production. It is important not to suppress the adrenal glands so long as to prevent them from producing cortisone on its own. For that reason, prednisone is usually given every 48 hours allowing a 12 hour period of time when the oral medication has exited the body and forcing the adrenal gland to produce on its own. The dog’s adrenal glands function primarily at night.