An Experimental Basis of Combined Antibiotic Action

The increasing number of available potent antimicrobial agents tempts the physician to use several of these drugs simultaneously in the same patient. This practice is often justified with the statement, "if one drug should not influence the disease-producing micro-organisms, the other one will." Such indiscriminate combined therapy has led to diminishing emphasis on specific etiologic diagnosis which should be the basis of antimicrobial treatment.1On the basis of the claim "if one drug is good, two should be better," combinations are frequently administered although little is known about their effect. To approach the problem rationally it is important to assemble experimental facts on the behavior of combinations of antimicrobial drugs. Better clinical management might be built on such a foundation. The present report, however, is limited strictly to the effects of drug combinations observed in the laboratory under controlled conditions and in no way implies that the same principles