Early empiric antibiotic therapy can significantly decrease the risk of mortality and infectious morbidity in patients with hematologic malignancies. Broad-spectrum antibiotics, usually a combination regimen of a beta-lactam and an aminoglycoside, have traditionally been employed against the wide variety of organisms that cause febrile episodes. However, since the 1970's, there has been a shift in epidemiology from Gram-negative to Gram-positive infections, against which traditional combination regimens have only limited efficacy. The carbapenems offer a suitable monotherapeutic alternative as they have a very broad spectrum of antibacterial activity, and equivalent efficacy and safety compared with combination regimes. Trials using imipenem/cilastatin have shown equal efficacy to ceftazidime but neurologic and gastrointestinal toxicity were observed at high doses (1 g 6-hourly). In the largest study to date, meropenem (1 g 8-hourly) provided effective, well tolerated monotherapy for patients with febrile neuropenia, equivalent to a regimen of ceftazidime plus amikacin. It is concluded that meropenem appears to be a realistic option for initial monotherapy in febrile neutropenic patients, providing therapy that is equivalent to a standard regimen of ceftazidime and amikacin.