Relationship between Risperidone and 9-hydroxy-risperidone Plasma Concentrations and CYP2D6 Enzyme Activity in Psychiatric Patients - Berecz, R; LLerena, A; de la Rubia, A; Gómez, J; Kellermann, M; Dorado, P; Degrell, I (Pharmacopsychiatry, 2002)