Trimethoprim and co-trimoxazole in the treatment of acute urinary tract infections: patient compliance and efficacy.

Patient compliance and drug efficacy and side-effects were compared in two groups of patients with symptoms of acute lower urinary tract infections. One group was treated with trimethoprim, one tablet (300 mg) once a day, and the other with co-trimoxazole, two tablets (160 mg trimethoprim, 800 mg sulphamethoxazole) twice a day; both treatments were prescribed for seven days. Patient compliance was significantly greater with trimethoprim: corrected percentage compliance rates were 97.5 per cent for trimethoprim and 79.1 per cent for co-trimoxazole (p<0.05). Trimethoprim and co-trimoxazole were of equivalent effectiveness in the control of symptoms. Side-effects were more frequent with co-trimoxazole, but the difference was not significant.