title: Postantibiotic effect of imipenem on Pseudomonas aeruginosa.
abstract: Imipenem (formerly N-formimidoyl thienamycin) and ceftazidime were investigated for their postantibiotic effect on Pseudomonas aeruginosa. Four strains of P. aeruginosa in the logarithmic phase of growth were exposed for 1 and 2 h to concentrations of antibiotics achievable in human serum. Recovery periods of test cultures were evaluated after dilution or addition of beta-lactamase. A consistent postantibiotic effect against all strains was obtained with imipenem but not with ceftazidime. Although ceftazidime did not have a postantibiotic effect, it did suppress the growth of the organisms at concentrations equivalent to one-third of the MIC. The clinical implications of these effects need further evaluation.
mesh_terms: D000583:Amikacin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002442:Ceftazidime / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D015378:Imipenem; D008826:Microbial Sensitivity Tests; D009070:Moxalactam / Q000494:pharmacology; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000254:growth & development*; D013845:Thienamycins / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D013997:Time Factors; D001618:beta-Lactamases / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D013845:Thienamycins; D015378:Imipenem; D000583:Amikacin; D002442:Ceftazidime; D001618:beta-Lactamases; D009070:Moxalactam