Which statement is true about the incidence of clozapine-associated neutropenia?

• A. 2.8% overall, 0.9% severe
• B. 0.5% overall
• C. 5% overall
• D. 1% overall

Answer: (A)

Clozapine carries a real risk of neutropenia, which is why guidelines emphasize regular blood monitoring. The typical data show neutropenia of any degree in about 2–3% of patients, with severe neutropenia (agranulocytosis) around 0.8–1%. The statement that neutropenia occurs in about 2.8% of patients overall and that severe cases are about 0.9% fits these commonly cited figures. That’s why this option is the best choice.

Because the risk is not negligible, monitoring is essential: baseline white blood cell count and absolute neutrophil count, then frequent checks early in treatment with clozapine and clear action thresholds for dose interruption or discontinuation if counts fall. The other rate figures don’t align with the typical risk estimates (being much lower or higher than the well-established range), which is why they’re not correct.