CYP2D6 and drug dependence: The reasons for the volunteers’ exclusion (n = 18) were: 12 W (10 having previous mental disorders [6 abuse of/dependence on drugs of abuse; 4 affective disorders]), 1 CYP2D6 PM phenotype, and 1 due to a positive drug screen test for cannabis and cocaine); and 3 M (2 CYP2D6 PM phenotype, and 1 with criteria of drug dependence).