Single dose therapy appears to offer the advantages of low cost, high compliance and comparable efficacy. Studies have confirmed that sing-dose therapy

Unlike single-dose antibiotic therapy, a three-day regimen reduces rectal carriage of gram-negative bacteria and is not associated with a high reecurrence rate. Thus three-day regimens appear to offer the optimal combincation of convenience, low cost and an efficacy comparable to that of seven-day or longer regimens but with fewer side effects. On the basis of cost and efficacy, trimethoprimsulfamethoxazole remains the antibiotic of choice in the treatment of uncomplications UTIs in young women. The use of fluoroquinolones produced better cure rates with less toxicity, but a greater overall cost. The use of fluoroquinolones as first-line therapy for uncomplicated UTIs should be discouraged, except in patients who cannot tolerate sulfonamides or trimethoprim, who have a high frequency of antibiotic resistance because of recent antibiotic treatment or who reside in an area in which significant resistance to trimethoprim-sulfamethoxazole has been noted. Three days is the optimal duration of treatment for uncomplicated cystitis.

A seven-day course should be considered in pregnant women, diabetic women and women who have had symptoms for more than one week and thus are at higher risk for pyelonephritis because of the delay in treatment.