Eighteen infants with severe hypernatremic dehydration secondary to acute gastroenteritis were rehydrated during the 1st day with an oral glucose electrolyte solution containing 60 mmol sodium/L at a mean rate of 120 ml/kg/24 h. These 18 children were safely treated with oral therapy alone. No convulsions were observed during treatment. The mean decrease in natremia was 0.32 mmol/L/h, which compared favorably with the mean fall in natremia of 26 other infants in similar initial conditions who were treated intravenously. The present study lends additional support to the opinion that a slow decrease in plasma sodium (less than 0.5 mmol/L/h) helps to avoid seizures during treatment. As no other untoward effects were observed, this study also confirms that oral solutions given at a slow rate can effectively replace intravenous fluids in the majority of such children.