Treatment of chronic idiopathic large-dowel diarrhea in dogs with a highlydigestible diet and soluble fiber: A retrospective review of 37 cases

The medical records of 37 dogs diagnosed with chronic idiopathic large-bowe l diarrhea were reviewed. The median age of affected dogs was 6 years. The median body weight was 13.9 kg. The median duration of clinical signs befor e diagnosis was 32 weeks. Diarrhea usually was intermittent and characteriz ed by increasing frequency, fecal mucus, hematochezia,and tenesmus. Vomitin g was common but usually much less frequent and severe than the diarrhea. A variety of stressful factors and abnormal personality traits were identifi ed. CBC and serum biochemistry usually were normal. Fecal examination rarel y identified parasites. Rectal cytology specimens were most often normal, b ut some dogs had increased numbers of neutrophils. The colonic mucosa often was normal during colonoscopy, but decreased numbers of lymphoid follicles were found in some dogs. Histopathologic evaluation found that colonic muc osa was within normal limits. Treatment with soluble fiber (Metamucil) adde d to a highly digestible diet (Hills i/d) resulted in a very good to excell ent response in most dogs. The median initial dosage of Metamucil was 2 tab lespoons (2 T) per day. In some dogs, the fiber dosage was reduced or elimi nated, or a grocery store brand of dog food was substituted, without causin g diarrhea to return.