In spite of the success of the ORS, there remained criticism from health workers and mothers that the original ORS solution did not stop diarrhea or reduce the duration of the episode. Hence, during the past 20 years, research has been undertaken to develop an "improved" ORS that would be safe and effective for treating or preventing dehydration in all types of diarrhea, and would also have other clinical benefits when compared with the standard ORS.

Studies have shown that the efficacy of ORS for treatment of children with acute diarrhea is improved by reducing its sodium concentration to 75 mEq/l, its glucose concentration to 75 mmol/l, and its total osmolarity to 245 mOsm/l. 11 This compares to the original solution which contained 90 mEq/l of sodium with a total osmolarity of 311 mOsm/l. There has been a concern that the original solution, which is slightly "hyperosmolar" when compared with plasma, may risk hypernatremia or an increase in stool output, especially in infants and young children.

The study results clearly describe the advantages of this new reduced osmolarity ORS solution in treating children with acute diarrhea:

It reduces stool output or stool volume by about 25% when compared to the original WHO UNICEF ORS solution,

It reduces vomiting by almost 30%,

It reduces the need for unscheduled IV therapy by more than 30%.