In cholera, the function of small intestine is affected resulting in increased secretion of electrolytes and water and their reduced absorption leading to profuse watery diarrhoea. The human colon has the capacity to absorb water and electrolytes. A number of recent studies have shown that short chain fatty acids (SCFAs) such as acetate, butyrate and propionate stimulates absorption of sodium in the colon, which is not affected by cyclic AMP. It has also been shown that SCFAs inhibits c-AMP mediated chloride secretion in the colon. Benefiber (partially hydrolyzed guar gum) is water soluble fibre, and when added to ORS it undergoes fermentation in the colon liberating SCFAs. SCFAs not only serves as metabolic fuel to the enterocytes but they also enhance colonic absorption of salts and water. Thus, they have potentials to reduce the severity of diarrhoea in patients with cholera. The aim of this study is to assess the efficacy of Benefiber-added WHO-ORS in the management of adults with cholera. In this randomized, controlled clinical trial, a total of 174 adult males with cholera would be studied. Study patients would be selected from those who attend the Dhaka Hospital of ICDDR,B with a history of diarrhoea of less than 24 hours and signs of severe dehydration. They would be rehydrated using intravenous fluid (cholera saline) over 4 hrs during which a stool specimen would be subjected for dark-field microscopy for identification of V. cholerae. Those identified to have cholera would be randomized in equal numbers to receive either: a) Benefiber (25 g/L) added WHO-ORS, b) Benefiber (50 g/L) added to the new formulation (Na+ 75, glucose 75, Cl- 65, K+ 20 mmol/L, citrate 10 mmol/L, osmolarity 245 mosmol/L) of WHO-ORS , or c) the same WHO-ORS but without Benefiber for maintenance of hydration until resolution of diarrhoea. All patients would be treated with a single, 300 mg dose of doxycycline capsules and would be provided with the standard hospital diets. Fluid intake (intravenous fluid, ORS, and plain water) and output (stool, urine, and vomit) will be measured for each 6-hourly periods of the study. Patients would be hospitalized until resolution of their diarrhoea. Stool output, intake of intravenous fluid and ORS, the duration of diarrhoea, and the proportion of patients requiring "unscheduled intravenous fluid therapy" would be compared between the treatment groups. If Benefiber is found effective, it would be possible to formulate improved ORS for better case management of cholera.