Nitrofurantoin for Group B Streptococcus UTI
Antimicrobial Activity and Clinical Evidence
- Nitrofurantoin has good in vitro activity against Group B Streptococcus (GBS) and is an appropriate treatment option for uncomplicated lower urinary tract infections caused by GBS, though clinical data specifically for GBS UTI is limited 1
- Nitrofurantoin achieves high urinary concentrations that exceed therapeutic levels by 25- to 100-fold, making it particularly effective for lower urinary tract infections 2
Special Considerations for GBS
- If GBS bacteriuria is detected during pregnancy at any concentration, this indicates a need for intrapartum antibiotic prophylaxis with penicillin or ampicillin, not treatment with nitrofurantoin during pregnancy 3, 4
- Pregnant women with GBS bacteriuria should receive intrapartum penicillin G (5 million units IV initial dose, then 2.5 million units IV every 4 hours) or ampicillin (2 g IV initial dose, then 1 g IV every 4 hours) during labor 4
- Antimicrobial agents should not be used before the intrapartum period to treat asymptomatic GBS colonization, as this is ineffective in preventing neonatal disease 3, 4
- For penicillin-allergic women at low risk of anaphylaxis, cefazolin is recommended for intrapartum prophylaxis 4, 5