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 NICE CKS.
- 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) NICE CKS.
- 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) NICE CKS.
In all cases, ensure a urine sample for culture and sensitivities has been sent before starting antibiotic treatment, if not already done NICE CKS. Review the choice of antibiotic when susceptibility testing results are available, using a narrow-spectrum antibiotic where possible NICE CKS. 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 NICE CKS. 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) NICE CKS. 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 NICE CKS. For catheter-associated UTIs, ideally remove or replace the indwelling urinary catheter before starting antibiotic treatment, if possible NICE CKS. 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 NICE CKS.