Diarrhea occurs frequently in the critically ill tube-fed population and may result from a multitude of causes. Despite the availability of antidiarrheal medications, diarrhea associated with enteral feedings remains a problem for clinicians and for the patients affected by it. We tested the hypothesis that administration of banana flakes would control diarrhea in critically ill patients receiving enteral feedings. Thirty-one patients with diarrhea and receiving enteral feedings were randomized to receive either banana flakes or medical treatment for diarrhea. Medical treatments included the use of pharmacological agents according to the discretion of the patient's physician or reducing feeding rates. Both banana flakes and medical treatments reduced the severity of diarrhea in critically ill tube-fed patients. Over the course of treatment, mean diarrhea scores were 21.64 +/- 7.81 for the banana flake group and 25.41 +/- 9.76 for the medical group. These differences were not statistically significant. Both groups achieved similar levels of nutrition support. The banana flake group had less diarrhea clinically, with 57% of the subjects diarrhea free on their last study day as opposed to 24% of the medically treated subjects. This occurred despite a threefold increase in the number of patients testing positive for Clostridium difficile toxin in the banana flake group. We conclude that banana flakes can be used as a safe, cost-effective treatment for diarrhea in critically ill tube-fed patients. Banana flakes can be given concurrently with a workup for C. difficile colitis, thereby expediting treatment of diarrhea.