Comparative study of three different dosing regimens of cefotaxime for treatment of gram-negative bacteremia.

Thirty-one patients with Gram-negative bacteremia with organisms susceptible to cefotaxime (CTX) (MIC of 1 microgram/ml or less) were randomized to receive 2 g of CTX every 6, 8, or 12 hr. Five-hour susceptibility studies were performed on a bacterial pellet obtained from the patient's positive blood culture vial. Thus, patients were enrolled within hours after Gram-negative organisms were demonstrated in their blood cultures. All bacteremias were cleared although two patients had unsatisfactory responses to therapy. Trough serum bactericidal levels were 1:2 or greater in all patients. This study supports that CTX can be used at an 8- or 12-hr intervals in selected patients with Gram-negative bacteremia.