Bactericidal Synergistic Effect due to Chloramphenicol-induced Inhibition of Staphyloccal Penicillinase

Abstract
A synergistic bactericidal effect of chloramphenicol and penicillin-G was observed with 17 of 20 .beta.-lactamase producing strains of Staphylococcus aureus. The synergism was due to chloramphenicol-induced inhibition of .beta.-lactamase production. With 7 of the strains the synergistic effect was operative only with subinhibitory concentrations of chloramphenicol, while higher concentrations produced antagonism.