CYP2D6 and schizophrenia: Of note, if a patient with schizophrenia receives adjunctive antidepressants that are also metabolized by CYP2D6 and CYP3A4 (e.g., Fluoxetine, Paroxetine, etc.), increases in the serum concentrations of both the antidepressant and aripiprazole may occur [1,9].