Nitrofurantoin (Macrobid) is used for UTIs in pregnant women for how many days?

• A. 3 days
• B. 5 days
• C. 7 days
• D. 10 days

Answer: (B)

Five days. The key idea is that for cystitis in pregnancy, nitrofurantoin is given for a short, focused course that reliably clears infection while limiting fetal exposure. Nitrofurantoin concentrates in the urine and is effective against common urinary pathogens like E. coli, so a five‑day regimen provides enough time to eradicate bacteria without unnecessary extra days of antibiotic use. A shorter three‑day course is generally not enough in pregnancy, while longer seven or ten days doesn’t improve outcomes and only increases the risk of adverse effects. The standard dosing is 100 mg taken twice daily for five days.