CYP2D6 and psychotic disorder: Of those prescribed a ‘CYP2D6-PGx antipsychotic’, it was observed that 75 (31%) patients had two or more transitions and that of these patients 56 (23%) would have met the criteria to offer a PGx test, based on current guidance (Van Westrhenen et al., 2021a), following the first two psychosis drug trials.