Neonatal Metabolic Acidosis after Intrauterine Exposure to Acetazolamide

Acetazolamide is a commonly used drug for intracranial hypertension. Teratogenic and metabolic effects of acetazolamide on a fetus have sparsely been reported. Here, we report a neonate presenting with hyperchloremic metabolic acidosis associated with maternal use of acetazolamide during pregnancy. Case description: A term female infant was born to a mother with normal prenatal course. During pregnancy, the mother was treated with acetazolamide for idiopathic intracranial hypertension. She presented with hyperchloremic metabolic acidosis soon after birth and was admitted to the neonatal intensive care unit for further evaluation and management. The serum bicarbonate and serum chloride concentrations were 12 mmol/L and 110 mmol/L respectively with normal remaining laboratory parameters. No other cause for metabolic acidosis was identified. Infant was treated conservatively with intravenous fluids and laboratory studies normalized over the next 48 hours. Conclusion: The safety of using acetazolamide during pregnancy is not well established. This case points to possible fetal metabolic side effects of in utero exposure to acetazolamide. Potential exposure to maternal medications should be considered while evaluating neonatal metabolic acidosis with normal physical examination.