PIP: A clinical study was carried out to assess the response of 46 infants to oral loads of carbohydrates after recovery from severe diarrhea. The response was measured by the increases in blood reducing sugars and by the variations in the stool pattern following administration of oral carbohydrates. Disaccharide oral loads were used in the test. During the acute stage of the illness, 38 of the 46 patients had exhibited intolerance to carbohydrates, as evidenced by the excretion of acid stools and/or stools with a greater than .25% carbohydrate content. Prompt improvement from diarrhea was induced by elimination of all lactose, disaccharides, and other carbohydrates from the diet. None of the infants had monosaccharide intolerance during the acute diarrheal stage. The carbohydrate oral loads were administered within 1 week after recovery and serially thereafter. Responses to sucrose and lactose loads were related to the degree of intolerance exhibited during the illness. In infants with diarrhea, the impaired carbohydrate metabolism is temporary. Oral feedings may be administered after cessation of profuse diarrhea and vomiting and after replacement of water and electrolytes. Patients should be back on a milk formula within 3-4 months, depending on the degree of carbohydrate intolerance exhibited during the illness.