Patients in intensive care units (ICUs) are at increased risk of developing nosocomial infections. This is of special concern in the immunocompromised patient, particularly with regard to multiresistant pathogens. We evaluated the effectiveness of cefepime 2 g bd in combination with amikacin 7.5 mg/kg bd for the treatment of severe bacterial infection in 118 ICU patients, including 113 patients with nosocomial lower respiratory tract infections (LRTI) (mean age, 51 years). Ninety-six per cent (108/113) of the LRTI patients required respiratory assistance and 12% (14/113) had associated septicaemia/bacteraemia. Eighty-four per cent (95/113) had clinical signs of sepsis and 35% (39/113) had features of septic shock. The mean Simplified Acute Physiologic Score (SAPS) was 12 at inclusion. Seventy-nine patients with LRTI were clinically and bacteriologically evaluable. The causative pathogens were representative of those usually isolated in ICUs: Staphylococcus aureus (19%); Pseudomonas aeruginosa (14%); and Klebsiella, Enterobacter and Serratia spp. (17%). The clinical cure rate was 86% (68/79) while the pathogen eradication rate was 91% (107/117). Of the patients with associated septicaemia/bacteraemia, 89% (8/9) of the pathogens were eliminated. Cefepime-amikacin combination therapy was well tolerated; two patients discontinued treatment due to rashes. Combination therapy with cefepime 2 g bd and amikacin 7.5 mg/kg bd appears safe and effective for the treatment of nosocomial pneumonia in patients hospitalized in ICUs. Further comparative controlled studies are justified.