 Efforts are continuing to improve the efficacy of oral rehydration solution in terms of reducing the severity stool volume and duration of diarrhoea enhancement of recovery. Antimicrobial peptides, produced by the epithelial cells, represent an important component of the innate immunity of all epithelial surfaces of the body including intestine. Induction of expression of antimicrobial peptides on epithelial cell surface, may thus hasten recovery from infectious diarrhoea. Isoleucine is an essential amino acid that is easily available and not very expensive, and its addition to oral rehydration solution might help early clearance of diarrhoeal pathogen by inducing secretion of antimicrobial peptide by the small intestinal epithelial cells. Additionally, it is expected to hasten recovery from diarrhoea by reestablishing the commensal bacteria. The aim of this pilot study is to assess if addition of isoleucine to oral rehydration solution induces secretion of antimicrobial peptide, help establish normal bacterial populations in the intestine, and favourably impacts the severity and duration of diarrhoea in young children. If the results are found encouraging, a therapeutic trial with adequate sample size would be justified. 