Forty hospitalized adult patients with gynecological infections were randomly assigned to treatment either with piperacillin alone (22 patients) or with the combination of gentamicin, clindamycin and penicillin G (18 patients). The aim of the study was to investigate the possibility of replacing a triple combination therapy with a single-agent broad spectrum antibiotic. Penicillin G was added for the coverage of enterococci. The median duration of treatment was 8 days for both groups. The daily dose for the administered drugs was 12g for piperacillin, 4mg/kg for gentamicin, 1.8g for clindamycin and 20 million units for penicillin G. The cure-improvement rate in the single agent therapy group was 90.9% and in the combination therapy group 94.4%. These differences were not statistically significant. No side effects were reported. It is concluded that single agent piperacillin is as effective as the combination therapy used in this study for the treatment of hospitalized gynecological infections.