Cephalexin is a broad spectrum antibiotic associated with Clostridium Difficile associated diarrhoea and would usually not be used when other choices are available.
Nitrofurantoin requires a Glomerular filtration rate of >45mL/min/1.73m2 If the patient has any renal problems this should be considered when making the decision
Compliance may be an issue as it is a QDS (four times a day dose)
Trimethoprim is available in a twice daily dose (BD)
Amoxycillin is a broader spectrum antibiotic (only used in about 30% of UTI) and although is suitable here, UTIs are usually treated with Trimethoprim or Nitrofurantoin as first line. Amoxycillin is a TDS (three times a day) dose.
Dose and duration – a 3 or 5 day course of antibiotics should be considered in an uncomplicated UTI.
In order to get some prescribing resources out there we intend to publish a series of prescribing problems on the website. The problems will appear at least weekly with the "answers" appearing a couple of days later. We'll use the standard exam stationery available on the LSE, but also available below in case you haven't got access to the LSE.