Subjective experience and striatal dopamine D2 receptor occupancy in patients with schizophrenia stabilized by olanzapine or risperidone

Objective: The authors' goal was to study the relationship between subjective experience during treatment with olanzapine or risperidone and dopamine D-2 receptor occupancy in stabilized patients with schizophrenia. Method: Subjective experience, psychopathology, and extrapyramidal symptoms were assessed, and D2 receptor occupancy was determined with [(123)]iodobenzamide single photon emission computed tomography, in 22 patients whose schizophrenia was stabilized by olanzapine or risperidone. Results: Subjective experience, depression, and negative symptoms were related to dopamine D-2 receptor occupancy, but extrapyramidal symptoms were not. Conclusions: These results provide preliminary evidence that negative subjective experience is related to high D-2 receptor occupancy. Longitudinal study is required because this relationship may have implications for dosing strategies.