COMPARISON OF POSTANTIBIOTIC EFFECTS OF IMIPENEM AND NETILMICIN ALONEAND IN COMBINATION AGAINST PSEUDOMONAS-AERUGINOSA

Imipenem (CAS 64221-86-9) as well as netilmicin (CAS 56391-57-2) at su prainhibitory concentrations induced the postantibiotic effects agains t three P. aeruginosa strains. Imipenem (2 x or 4 x minimal inhibitory concentration (MIC)) showed postantibiotic effects in the range of 0. 3-1.6 h and 0.9-4.0 h. Netilmicin at the same concentrations produced postantibiotic effects of 3.0-3.8 h and 3.5-4.5 h. Postantibiotic effe cts manifested by imipenem (2 x or 4 x MIC) + netilmicin (2 x MIC) com bination were somewhat longer (in the range of 4.6-4.9 h and 5.8-7.4 h ) than the mathematical sum of postantibiotic effects induced by drugs alone (in the range of 4.1-4.7 h and 4.7-7.0 h).