A randomized, multicenter clinical trial comparing two oral rehydration solutions (ORS) with different sugar content and total osmolality was carried out in France. Solution A had 168 mmol/L of sugar and a total osmolarity of 326 mosm/kg; solution D had 90 mmol/L of sugar and a total osmolarity of 240 mosm/kg. Weight gain, stool output, and biologic variables were analyzed. This interim analysis included 49 infants (27 in group A and 22 in group D). Patients in both groups gained weight without any significant difference between the two ORS. Between admission and day 4, the overall number of stools and the number of liquid stools decreased. Laboratory values were within the normal range on admission and remained unchanged. The weight increase during the first 24 hours and the reduced frequency of stools was similar in both groups.