Using nitrofurantoin while breastfeeding a newborn

Question: My patient has a urinary tract infection and is currently breastfeeding. Her son is only 3 weeks old. Is nitrofurantoin a safe antibiotic for treatment? Answer: The use of nitrofurantoin in breastfeeding mothers is generally safe, as only small amounts transfer into the breast milk. Despite the lack of documented reports, there is a risk of hemolytic anemia in all newborns exposed to nitrofurantoin owing to their glutathione instability, especially in infants with glucose-6-phosphate dehydrogenase deficiency. Although some suggest that nitrofurantoin be avoided in infants younger than 1 month, studies have noted that glutathione stability might be established by the eighth day of life. In infants younger than 1 month, an alternative antibiotic might be preferred; however, if an alternative were not available, the use of nitrofurantoin would not be a reason to avoid breastfeeding. In any such case the suckling infant should be monitored by his or her physician.