Which statement best reflects the incidence data for clozapine-associated neutropenia?

Which statement best reflects the incidence data for clozapine-associated neutropenia?

• A. 0.5%, severe 0.1%
• B. 2.8%, severe 0.9%
• C. 5%, severe 2%
• D. 1%, severe 0.1%

Answer: (B)

Clozapine carries a risk of neutropenia, with overall neutropenia occurring in a few percent of treated patients and severe neutropenia (which can progress to agranulocytosis) in about one in a hundred or so. The figure of 2.8% for neutropenia with about 0.9% becoming severe fits well with these typical estimates, showing that most neutropenia events are not extreme but still require careful monitoring and sometimes stopping the medication. This is why regular absolute neutrophil counts are required during clozapine treatment to catch drops early and protect against serious complications. Other options fall outside these commonly observed ranges, either underestimating or overestimating the frequency of neutropenia and its severe form.

Clozapine carries a risk of neutropenia, with overall neutropenia occurring in a few percent of treated patients and severe neutropenia (which can progress to agranulocytosis) in about one in a hundred or so. The figure of 2.8% for neutropenia with about 0.9% becoming severe fits well with these typical estimates, showing that most neutropenia events are not extreme but still require careful monitoring and sometimes stopping the medication. This is why regular absolute neutrophil counts are required during clozapine treatment to catch drops early and protect against serious complications. Other options fall outside these commonly observed ranges, either underestimating or overestimating the frequency of neutropenia and its severe form.