How should I manage a patient with suspected urinary tract infection who is allergic to first-line antibiotics?

When managing a patient with a suspected urinary tract infection (UTI) who is allergic to first-line antibiotics, consider prescribing second-line options if first-line treatments are contraindicated or not tolerated ¹.

• For uncomplicated lower UTI in women (aged 16 years onwards): If nitrofurantoin or trimethoprim (first-line options) are contraindicated or not tolerated, consider prescribing nitrofurantoin (if not used first-line), pivmecillinam (400 mg initial dose, then 200 mg three times a day for a total of 3 days), or fosfomycin (3 g single dose sachet) ¹.
• For suspected UTI with a catheter in situ (women aged 16 years onwards): If first-line treatments (nitrofurantoin, trimethoprim, or amoxicillin if susceptible) are contraindicated or not tolerated, consider pivmecillinam (400 mg initial dose, then 200 mg three times a day for a total of 7 days) ¹.

In all cases, ensure a urine sample for culture and sensitivities has been sent before starting antibiotic treatment, if not already done ¹. Review the choice of antibiotic when susceptibility testing results are available, using a narrow-spectrum antibiotic where possible ¹. Advise the patient to seek urgent medical review if symptoms worsen rapidly or significantly at any time, or do not improve within 48 hours of starting antibiotic treatment ¹. Also, advise on self-care measures for symptom relief, such as short-term over-the-counter simple analgesia (e.g., paracetamol or ibuprofen) and maintaining adequate hydration (aim for 1.5 L of water a day if no contraindications) ¹. Urgent hospital admission should be arranged if there are severe systemic symptoms or signs suggesting a serious complication (e.g., pyelonephritis or sepsis), or if the patient is unable to tolerate or adhere to treatment in primary care ¹. For catheter-associated UTIs, ideally remove or replace the indwelling urinary catheter before starting antibiotic treatment, if possible ¹. If the catheter has been in situ for 7 days at the onset of UTI and is still needed, it should be checked for leakage or blockage and replaced if it cannot be removed ¹.