Steady-state pharmacokinetics of imipenem in febrile neutropenic cancer patients.

We ascertained the pharmacokinetics of imipenem in febrile granulocytopenic cancer patients. The values observed were both different from and significantly more variable than those observed in normal volunteers. Free drug concentrations exceeded the MIC for 90% of Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus strains for greater than 6 h. The MIC for 90% of Pseudomonas aeruginosa strains was exceeded for 4 h. Because imipenem induces a 2-h postantibiotic effect in P. aeruginosa, it is promising as single-agent empiric therapy in this setting.