The relationship between subjective well-being and dopamine D2 receptors in patients treated with a dopamine partial agonist and full antagonist antipsychotics.

Antipsychotic drugs produce unpleasant subjective experiences, which have been associated with high levels of dopamine D2 receptor occupancy. Aripiprazole is a partial agonist antipsychotic, which is hypothesized to produce a different subjective experience profile compared to standard D2 antagonist antipsychotics. The aim of this study was to compare the effect of D2 occupancy produced by a partial agonist antipsychotic (aripiprazole) to that of antagonist antipsychotics (risperidone or olanzapine) on the subjective well-being of patients. Subjective well-being was measured using the Subjective Well-being under Neuroleptics Scale (SWN) and was related to dopamine D2 receptor occupancy using [11C]raclopride PET. Patients that were switched to aripiprazole showed improvement in their subjective well-being from 79.80 (S.D.=16.08) to 89.90 (S.D.=15.33), an effect that was sustained for 6 months. This sustained improvement was observed despite very high levels of DA D2 occupancy (82-99%), in contrast to the effects of antagonist antipsychotics on subjective well-being.