Prochloraz is an imidazole antifungal that inhibits ergosterol biosynthesis via inhibition of the cytochrome P450-dependent 14α-demethylation of lanosterol, which results in disruption of the fungal cell membrane and cell death. It inhibits human placenta microsomal aromatase in vitro (IC50 = 40 nM). Prochloraz also acts as an antagonist of the estrogen receptor (ER) and androgen receptor (AR) (IC50s = 25 and 4 μM, respectively) as well as activates the aryl hydrocarbon receptor (AhR; EC50 = 1 μM). In vivo, prochloraz (250 mg/kg) reduces the weight of seminal vesicles in intact male rats and of seminal vesicles, ventral prostate, and bulbourethral glands in castrated testosterone-treated male rats. It also reduces testosterone levels and increases progesterone levels in male rat pups following administration of a 30 mg/kg per day dose to pregnant females during gestation. Formulations containing prochloraz have been used to control fungal growth in mushroom cultivation.