• As part of an intensive drug surveillance program, we identified rates and associated risk factors for hyperglycemia related to intravenous 10% dextrose solution in a population of 1,157 newborns in two neonatal intensive care units. Hyperglycemia related to 10% dextrose solution was observed in 64 exposed infants (5.5%), a rate similar to that observed for hypoglycemia (6.7%) in this population. There was a highly significant trend toward an increasing risk of hyperglycemia with decreasing body weight, such that the risk of hyperglycemia among infants weighing less than 1,000 g was 18 times greater than the risk among infants weighing more than 2,000 g. The risk of hyperglycemia also increased with increasing dextrose dose. The effects of weight and dose were independent. Certain measures of disease severity also were associated with increased risks of hyperglycemia. Because increases in blood glucose levels may affect renal function or possibly lead to intraventricular hemorrhage, it is important that glucose levels in neonates receiving 10% dextrose solution be carefully monitored, and the total dextrose dose be adjusted accordingly.