Abstract
The clinical benefit of the atypical antipsychotic drug clozapine may be related to a combined effect on D2 and 5-HT2 receptors. To examine the basis for this hypothesis, positron emission tomography (PET) and the radioligand [11C]N-methylspiperone were used to determine cortical 5-HT2 receptor occupancy in three psychotic patients treated with 125 mg, 175 mg and 200 mg clozapine daily. The uptake of [11C]N-methylspiperone in the frontal cortex was very low compared to that in neuroleptic naive schizophrenic patients. 5-HT2 receptor occupancy calculated in the clozapine treated patients was 84%, 87% and 90%. The results show that clinical treatment with clozapine induces a high 5-HT2 receptor occupancy in psychotic patients at a low dose level.
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Nordström, AL., Farde, L. & Halldin, C. High 5-HT2 receptor occupancy in clozapine treated patients demonstrated by PET. Psychopharmacology 110, 365–367 (1993). https://doi.org/10.1007/BF02251294
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DOI: https://doi.org/10.1007/BF02251294