Abstract: An oral rehydration solution contains indigestible oligosaccharides. Diarrhea related dehydration requires fluid and electrolyte replacement. The primary etiology of antibiotic-associated diarrhea (also known as pseudomembranous colitis) has been recognized as Clostridium difficile. It is believed that the indigenous microflora of a healthy individual suppresses the normally present C. difficile. However, when the indigenous microflora are disrupted (e.g., during antibiotic treatment) overgrowth of C. difficile may occur causing diarrhea and colitis. Treatment of diarrhea related to C. difficile with rehydration therapy and antibiotics has proven effective, but many times relapse occurs. It has been suggested that normalization of the microflora will inhibit C. difficile relapse. Indigestible oligosaccharides have been shown to inhibit C. difficile infection.