STUDIES ON ANTIBIOTIC SYNERGISM AND ANTAGONISM

Abstract
THE DYNAMICS of antimicrobial action are known to some extent for the "older" antibiotics, particularly penicillin. Data are being accumulated at present on the "newer" antibiotics, aureomycin, chloramphenicol and terramycin. Relatively little information, however, is available on the results of simultaneous action of two or more antibiotics. Such basic information is desirable particularly in view of the increasing trend for multiple antibiotic therapy in medical practice. Two antibiotics acting simultaneously might be additive, synergistic, antagonistic or without any effect on each other. This spectrum of possible combinations has been shown to exist for various sulfonamides1and has been suggested for antibiotics.2Synergistic effects have been demonstrated for combinations of penicillin and streptomycin in their action against enterococci in vitro3and against enterococcic human infections.4In some other infections (e. g., brucellosis) it has also been shown that combinations of antibiotics can achieve results unobtainable with any