Inclusion Criteria:  Women of 18 years of age or older, with clinical features of uncomplicated community-acquired lower urinary tract infection including:  At least one of four key symptoms of lower urinary tract infection: dysuria, urgency including nycturia, frequency, and suprapubic tenderness that could be attributed to an uncomplicated lower urinary tract infection, and no alternative explanation (i.e. symptoms suggestive of sexually-transmitted infection or vulvovaginitis), and A urine dipstick analysis positive for either nitrites or leukocyte esterase.  Exclusion Criteria:  Male sex High suspicion of pyelonephritis (i.e. fever ≥ 37.5°C or flank pain/tenderness) Any condition that may lead or predispose to complicated urinary infection (i.e. indwelling urinary catheter, pregnancy, immunosuppressive therapy, abnormal urinary tracts, recurrent urinary tract infection, severe neurological disease affecting the bladder) Pregnancy or planned pregnancy Symptoms consistent with urinary tract infection in the preceding 4 weeks Patients taking long-term antibiotic prophylaxis Ongoing antibiotic therapy or use of any systemic antibiotic in the previous 7 days Symptoms correlating with differential diagnosis (i.e. vaginal discharge or pain) Hypersensitivity or allergy to β lactams, nitrofurantoin and/or fosfomycin Moderate to severe chronic renal insufficiency Pre-existing polyneuropathy History of lung or liver reaction or peripheral neuropathy after previous use of nitrofurantoin Glucose-6-phosphate dehydrogenase deficiency Porphyria or systemic primary carnitine deficiency or of the type organic aciduria (i.e. methylmalonic aciduria and propionicacidaemia) Esophageal stricture Current intake of allopurinol or probenecid or valproate Currently part of another randomized clinical trial Previous enrolment in the proposed study Patients living in long-term institutions; and/or Difficulty in conducting scheduled follow-up visits