Nitrofurantoin: an update.

Nitrofurantoin has been in clinical use for more than 35 years for the treatment of urinary tract infections (UTIs). In particular, it has been used to treat acute uncomplicated UTIs, recurrent urinary tract infections, and asymptomatic bacteriuria of pregnancy. Most recently, it has been used for both prophylaxis and treatment of nosocomial infections related to urinary tract instrumentation. Nitrofurantoin is being "rediscovered" for urinary tract infections in obstetrics and gynecology because of its continuing safety record and lack of associated R-factor resistance, compared to recently introduced antimicrobials.