The in vitro activity of cefpodoxime, an oral cephalosporin ester, against 792 bacterial isolates representing 36 species was evaluated in comparison to that of ciprofloxacin and trimethoprim/sulfamethoxazole (TMP/SMX). Cefpodoxime inhibited the majority of Streptococcus spp., Haemophilus influenzae and Proteus mirabilis at a concentration of less than or equal to 0.12 microgram/ml. It was also active against Citrobacter diversus, Escherichia coli, Klebsiella spp., Proteus vulgaris, Serratia marcescens and methicillin-susceptible Staphylococcus aureus isolates. Overall, cefpodoxime appeared to be less active than ciprofloxacin and TMP/SMX against many pathogens common in cancer patients.