Dissociation from D2 is slower for which group of drugs compared to clozapine and quetiapine?

Dissociation from D2 is slower for which group of drugs compared to clozapine and quetiapine?

• A. Asenapine, olanzapine, risperidone, ziprasidone
• B. Clozapine and quetiapine
• C. Risperidone and ziprasidone
• D. Aripiprazole and ziprasidone

Answer: (A)

D2 receptor dissociation rate, or how quickly a drug leaves the D2 receptor, shapes how long D2 blockade lasts. Clozapine and quetiapine disengage from D2 relatively quickly, so their D2 occupancy falls faster and they tend to cause fewer extrapyramidal symptoms (EPS) despite good antipsychotic effects—partly because their therapeutic actions rely on other receptor interactions (like 5-HT2A antagonism). The group that dissociates more slowly from D2—asenapine, olanzapine, risperidone, and ziprasidone—stays bound longer, producing sustained D2 blockade. This longer residence time explains why they’re associated with slower dissociation from D2 compared with clozapine and quetiapine.

D2 receptor dissociation rate, or how quickly a drug leaves the D2 receptor, shapes how long D2 blockade lasts. Clozapine and quetiapine disengage from D2 relatively quickly, so their D2 occupancy falls faster and they tend to cause fewer extrapyramidal symptoms (EPS) despite good antipsychotic effects—partly because their therapeutic actions rely on other receptor interactions (like 5-HT2A antagonism). The group that dissociates more slowly from D2—asenapine, olanzapine, risperidone, and ziprasidone—stays bound longer, producing sustained D2 blockade. This longer residence time explains why they’re associated with slower dissociation from D2 compared with clozapine and quetiapine.