Involvement of CYP3A4 in the metabolism of bromperidol in vitro.

In this study, human cytochrome P450 isoenzymes (CYP1A2, CYP2C19, CYP2D6, and CYP3A4) expressed in a cell line were used to elucidate their roles in the metabolism of bromperidol. We found that CYP3A4 catalyzes the N-dealkylation of bromperidol and its metabolite, reduced bromperidol. CYP3A4 also catalyzes the dehydration of bromperidol to bromperidol 1,2,3,6-tetrahydropyridine, metabolizes bromperidol to bromperidol pyridinium, and catalyzes the oxidation of reduced bromperidol back to bromperidol. CYP1A2, CYP2C19, and CYP2D6 do not catalyze these reactions.