Comparative efficacies of pivmecillinam and ampicillin in acute shigellosis

The clinical efficacies of pivmecillinam and ampicillin were compared in a randomized double-blind trial in the treatment of acute shigellosis. Of 44 adult male patients, all culture positive for Shigella strains, 22 patients received 400 mg of pivmecillinam and 22 patients received 500 mg of ampicillin every 6 h. Both drugs were administered orally for 5 days. Four patients receiving ampicillin were infected with Shigella strains that were resistant to ampicillin but susceptible to pivmecillinam, and two patients receiving pivmecillinam were infected with Shigella strains resistant to both ampicillin and pivmecillinam. The mean duration of diarrhea in all patients receiving pivmecillinam was 3.3 days compared with 4.5 days in patients receiving ampicillin (P less than 0.05). When patients infected with…