Can we use metronidazole during pregnancy and breastfeeding? Putting an end to the controversy

QUESTION Two of my patients have been diagnosed with giardiasis, and I woul d like to treat them with the drug of choice for this infection, metronidaz ole (Flagyl(R)). One of them is 6 weeks pregnant and the other is breastfee ding a 2-month-old infant, and I have received conflicting information abou t the safety of this drug during pregnancy and breastfeeding. What should I do? ANSWER Although metronidazole has been on the market for almost 40 years, i ts use remains controversial during pregnancy and breastfeeding. Recent evi dence has shown, however, that this drug is not associated with adverse eff ects during either pregnancy or breastfeeding.