Antimicrobial agents in urinary tract infections.

Urinary tract infections are commonly encountered in clinical practice and are usually readily treatable. Although many antimicrobial agents that have been available for some time remain effective in the eradication of bacteriuria, the recent introduction of the fluoroquinolone norfloxacin represents an important addition to the therapeutic armamentarium. The efficacy of single-dose therapy with antimicrobial agents such as trimethoprim-sulfamethoxazole or amoxicillin has been shown to be similar to that with conventional (7- to 10-day) treatment in women with uncomplicated lower urinary tract infections. The long-term administration of agents such as trimethoprim-sulfamethoxazole or nitrofurantoin in low doses is usually effective for suppression or prophylaxis of recurrent bacteriuria.