Bacampicillin and ampicillin in urinary tract infections: a double-blind comparison of efficacy and tolerance.

A total of 100 hospitalized patients with upper and lower urinary tract infections were treated with bacampicillin or ampicillin. The treatment was double-blind and 50 patients were randomly allocated to each group, receiving 800 mg of bacampicillin or 2 g of ampicillin t. i. d. for ten days. The distribution by age and sex was similar in the two groups. Assessments of therapeutic response and tolerance were made two and six weeks after initiation of therapy. In 89% of the patients treated with bacampicillin and 68% of the ampicillin-treated patients both the bacteria and the symptoms were eliminated at the first follow-up visit three days after end of therapy. Relapse of reinfection occurred in 44% of the ampicillin-treated patients as compared to 7% in the bacampicillin-treated patients. Side-effects occurred significantly less frequently with bacampicillin compared with ampicillin (p less than 0.05). Treatment had to be stopped on account of side-effects in 16 patients treated with ampicillin compared with only four patients treated with bacampicillin.