What finding indicates a client on clozapine is experiencing an adverse effect of the medication?

The correct answer identifies a potential adverse effect associated with clozapine, which can cause agranulocytosis, a serious drop in white blood cell (WBC) counts that increases the risk of infection. A WBC count of 2,800/mm³ is concerning because it is below the normal range for white blood cells, typically between 4,500 to 11,000/mm³. Clozapine necessitates careful monitoring of the blood cell counts due to this risk. If a patient's WBC count falls below a certain threshold, it may indicate that the medication is causing an adverse effect requiring immediate intervention.

In contrast, weight loss, a heart rate of 64/min, and insomnia may occur in clients taking various medications, including clozapine, but they do not directly reflect the life-threatening effects associated with hematologic changes caused by the drug. Therefore, while they should still be monitored for overall health and treatment efficacy, they are not the primary indicators of a severe adverse effect linked to clozapine use.