CYP2D6*45x2 is assigned increased function based on limited evidence. CYP2D6*45 is assigned normal function (15768052; 24647041). Therefore, consensus among experts was increased function with an activity value of 2 based on limited evidence as it was determined the phenotypes containing a duplication of this allele would demonstrate greater protein expression and enzyme activity than that of the nonduplicated allele and be clinically distinct from phenotypes comprising normal function alleles.