Adult

Bacteriuria, asymptomatic (pregnant)

If in doubt about choice of agent due to allergy, drug interactions, resistant organisms or contraindications, then the case should be discussed with ID/Micro

Treat for 5 days. For selected or complex patient, e.g abnormal urinary tract, ureteric stent, renal calculi, reflux nephropathy, urinary diversion, may extend to 7 days.

For pregnant women with solid organ transplant see UTI: out-patient setting (Transplant)

Preferred - Empirical

nitrofurantoin 50mg po qds. AVOID after 37+0 weeks of gestation or if delivery is thought to be imminent due to potential risk of neonatal haemolysis.

Caution: Do not use if eGFR is under 45 ml/min/1.73m2

Adverse effects have been reported with nitrofurantoin see Nitrofurantoin MHRA drug safety updates

Alternative - Empirical

cefalexin 500mg po bd

Treatment according to culture and sensitivity in the following order of preference

amoxicillin 500mg po tds

If resistant to amoxicillin: nitrofurantoin 50mg po qds. AVOID after 37+0 weeks of gestation or if delivery is thought to be imminent due to potential risk of neonatal haemolysis. Caution: Do not use if eGFR is under 45 ml/min/1.73mAdverse effects have been reported with nitrofurantoin see Nitrofurantoin MHRA drug safety updates

If resistant to nitrofurantoin: cefalexin 500mg po bd  

If resistant to cefalexin: trimethoprim 200mg po bd (avoid in first trimester1)

Additional information

1. Avoid trimethoprim if possible in the 1st trimester due to the risk of neural tube defects in the fetus; if given, supplement with folic acid 5 mg OD.

Editorial Information

Last reviewed: 01 Apr 2024