Diarrhea is distinguished by prevalence of bowel movement accompanied by a loose consistency of stools, resulting from hyper peristalsis of the small intestine or colon, Diarrhea is a major challenge among infants and growing children. The study was carried out to assess the result of combined treatment of vitamin C and loperamide on intestinal Na+ , K+ - ATPase, alkaline phosphatase, and lipid peroxidation in castor oil induced diarrheal wistar rats. A total of 18 wistar rats weighing 180-200g were randomly divided into 6 groups, (Group 1 Normal control no castor oil, no treatment administered, Group 2 Experimental control were given castor oil 3.0 ml/kg body weight with no treatment, Group 3 Standard control were given castor oil 3.0 ml/kg body weight + loperamide, Group 4 Treatment 1 were administered 3.0 ml/kg body weight + 25 mg/kg combined effect of vitamin C and loperamide, Group 5 Treatment 2 were administered 3.0 ml/kg body weight + 50 mg/kg combined effect of vitamin C and loperamide, and Group 6 were administered 3.0 ml/kg body weight + 100 mg/kg combined effect of vitamin C and loperamide)with 3 rats per group; the experiment lasted for 24 hours. The action of intestinal alkaline phosphatase, Na+ , K+ -ATPase and malondialdehyde were determined. Descriptive statistical analysis was adopted using SPSS version 20.Combined effect of vitamin C and loperamide significantly (p<0.05) lowered the elevated levels of malondialdehyde caused by castor oil induced diarrhea; the Na+ , K+ - ATPase intestinal activity treatment with both vitamin C and loperamide significantly elevated the activity of Na+ , K+ ATPase when compared with the normal control, but both treatments (loperamide alone and vitamin C plus loperamide were not significantly different (p<0.05) to themselves. However, at 50 mg/kg body weight of combined effect of vitamin C and loperamide it showed significant difference in the action of intestinal alkaline phosphatase. Findings of this study therefore, indicate that a combined effect of loperamide and vitamin C will be an effective therapeutic agent in the management of diarrhea by scavenging of free radicals generated in the cause of diarrheal to reduce lipid peroxidation

Keywords : Diarrhea, Sodium and Potassium Ion Atpase, Alkaline Phosphatase, Lipid Peroxidation, Vitamin C, Antioxidant, Reactive Oxygen Species, and Castor Oil.