How should I manage a patient with recurrent urinary tract infections, and when should I consider prophylactic antibiotics?

Management of recurrent urinary tract infections (UTIs) depends on the patient's age, sex, and clinical context.

For adults with recurrent lower UTIs, first-line prophylactic antibiotic options include trimethoprim or nitrofurantoin, given either as a single dose when exposed to a trigger or as a low-dose nightly regimen. Specifically, trimethoprim 100 mg at night or nitrofurantoin 50–100 mg at night (if eGFR ≥45 mL/min/1.73m2) are recommended. If these are unsuitable, amoxicillin or cefalexin may be used as second-line options, with antibiotic choice guided by recent culture and susceptibility results and local policies. When prescribing prophylaxis, use a different antibiotic than that used for acute treatment to reduce resistance risk ¹,².

Prophylactic antibiotics should be considered in patients with recurrent UTIs who have not adequately improved with behavioural and personal hygiene measures, vaginal oestrogen (if applicable), or single-dose antibiotic prophylaxis. The decision to start or continue prophylaxis should involve discussion about the risks of antimicrobial resistance and adverse effects, and be reviewed at least every 6 months ¹,².

In women and trans men with a female urinary system, methenamine hippurate (1 g twice daily) may be considered as an alternative to daily antibiotic prophylaxis if recurrent UTIs persist despite other measures, but specialist advice should be sought before use, especially in pregnancy or complicated cases ².

For children with recurrent UTIs, prophylactic antibiotics may be considered after specialist assessment and investigations, particularly if behavioural and hygiene measures are ineffective. Preferred agents include trimethoprim or nitrofurantoin (if eGFR ≥45 mL/min), with cefalexin or amoxicillin as alternatives. Prophylaxis is not routinely recommended after a first UTI and should be guided by specialist advice, taking into account risks and benefits ³,⁴.

In people with neurogenic lower urinary tract dysfunction, routine antibiotic prophylaxis is not recommended but may be considered in those with frequent or severe UTIs after investigating and addressing underlying causes, with regular review of ongoing need ⁵.

Summary of when to consider prophylactic antibiotics:

• Recurrent UTIs not controlled by behavioural and hygiene measures.
• After specialist assessment in children with recurrent UTIs.
• In adults with frequent recurrent UTIs, after discussing risks and benefits.
• In neurogenic bladder patients with frequent/severe infections, after excluding treatable causes.

Regular review of prophylaxis efficacy, adverse effects, and antimicrobial resistance risk is essential, with advice to seek prompt treatment for acute UTI symptoms and consideration of rotating antibiotics according to local policies ¹,²,³,⁵.