The preparation and antifungal properties of 1-[4-(4-chlorophenyl)-2-(2,6-dichlorophenylthio)-n-butyl]-1H-imidazole nitrate 1 are described. It is particularly effective against in vivo Candida albicans infections (mice), maintaining good activity down to 0.25% formulation strength and showing unusually low reinfection rates after treatment is ended.