Risperidone-associated adverse drug reactions and CYP2D6 polymorphisms in a South African cohort.

Background: Contradictory information exists regarding the influence of CYP2D6 polymorphisms on adverse drug reactions (ADRs) (extrapyramidal symptoms (EPS) and weight gain) related to risperidone treatment. This prompted us to evaluate the influence of CYP2D6 genetic variation in a cohort of South African patients who presented with marked movement disorders and/or weight gain while on risperidone treatment.

Methods: Patients who were experiencing marked risperidone ADRs were recruited from Weskoppies Public Psychiatric Hospital.