Remission of severe tardive dyskinesia in a schizophrenic patient treated with the atypical antipsychotic substance quetiapine.

In a single inpatient case study, a schizophrenic patient with tardive dyskinesia after prolonged treatment with typical neuroleptics was treated with the new atypical neuroleptic quetiapine, a dibenzothiazepin-derivative. Within 2 weeks of treatment with quetiapine, symptoms of tardive dyskinesia improved; 10 weeks after starting treatment tardive dyskinesia stopped completely. Over the same period, dopamine D2 receptor occupancy decreased substantially, as measured by IBZM-SPECT after 14 and 77 days of treatment.