Which outcome is most closely associated with D2 occupancy around 50-75%?

Which outcome is most closely associated with D2 occupancy around 50-75%?

• A. EPS
• B. Maintenance dosing
• C. Hyperprolactinemia
• D. Clozapine monitoring

Answer: (C)

D2 receptor occupancy in the tuberoinfundibular pathway directly influences prolactin regulation. When blockade reaches around half to three-quarters of receptors, dopamine’s inhibitory control over prolactin is lifted enough to cause noticeable prolactin elevation. So hyperprolactinemia is the most likely outcome at this occupancy range. Extrapyramidal symptoms rise with even higher occupancy, generally above the 70–80% mark. Clozapine monitoring is driven by agranulocytosis risk and isn’t tightly tied to this mid-range D2 occupancy, and maintenance dosing isn’t about a specific D2 blockade effect.

D2 receptor occupancy in the tuberoinfundibular pathway directly influences prolactin regulation. When blockade reaches around half to three-quarters of receptors, dopamine’s inhibitory control over prolactin is lifted enough to cause noticeable prolactin elevation. So hyperprolactinemia is the most likely outcome at this occupancy range. Extrapyramidal symptoms rise with even higher occupancy, generally above the 70–80% mark. Clozapine monitoring is driven by agranulocytosis risk and isn’t tightly tied to this mid-range D2 occupancy, and maintenance dosing isn’t about a specific D2 blockade effect.