Therapy for experimental intraabdominal sepsis: comparison of four cephalosporins with clindamycin plus gentamicin.

An experimental model of intraabdominal sepsis in rats was used for evaluation of treatment with four cephalosporins: cephalothin, cefazolin, cefoxitin, and cefamandole. Doses were 115 mg of each of the cephalosporins/kg and, in additional experiments, 350 mg of cephalothin or cefazolin/kg. Response to treatment was evaluated by mortality rate and the incidence of intraabdominal abscess. All four cephalosporins and gentamicin produced a similar reduction in mortality rates. There was a marked variation in incidence of abscess dependent upon the cephalosporin selected and the dosage tested. Regimens most effective in reducing abscesses were clindamycin, low-dose cefoxitin, or high-dose cephalothin.