ANTI-MICROBIAL EFFECT OF COMBINATIONS OF COLISTIN METHANESULFONATE AND CHLORAMPHENICOL. I IN VITRO EFFECT

Abstract

Antimicrobial activity in vitro of colistin methanesulfonate and chloramphenicol was studied, using gram-negative enterobacteria and Staphylococcus aureus with various drug-resistance patterns and serotypes or phage types.A synergistic growth inhibitory action of both drugs against most of the gram-negative bacteria was demonstrated by a qualitative method and confirmed by a quantitative determination and statistical evaluation. It was also found that the combined action of both drugs obviously suppressed the development of drug resistant mutants of gram-positives as well as of gram-negativemicroorganisms.