In vitro fungistatic and fungicidal activities of voriconazole were evaluated against 114 isolates of Candida spp. MICs were determined using the NCCLS M27-A2 broth microdilution method. Minimum fungicidal concentrations (MFCs) were defined as the lowest drug concentrations that yielded < or = 5 colonies (> or = 98% killing activity). The fungicidal activity could be only evaluated against 45.6% of the isolates (52 of 114 isolates) because trailing growth occurred, and 30 of these 52 isolates (57.69%) showed MFC values < or = 1 mg/l. There was little or no fungicidal activity against C. albicans and C. tropicalis. In contrast, all C. krusei were killed by 1-2 mg/l voriconazole. In conclusion, our data show that the fungicidal effect of voriconazole against Candida spp. is species dependent.