During a follow-up visit a client taking clozapine reports symptoms of persistent sore throat and fever. What should be the nurse's priority action?

Choice A reason: While clozapine may eventually be discontinued if laboratory results confirm a dangerous drop in white blood cells, the nurse does not have the prescriptive authority to switch medications. The immediate priority is diagnostic confirmation of the patient's hematological status rather than an unauthorized change in the treatment regimen. Choice B reason: Advising increased fluid intake is a supportive measure for general illness but fails to address the potentially lethal underlying cause of the symptoms. In the context of clozapine therapy, a sore throat and fever are "red flag" indicators of agranulocytosis, which cannot be treated with simple hydration. Choice C reason: Clozapine carries a black box warning for agranulocytosis, a severe reduction in the absolute neutrophil count (ANC). Fever and sore throat are primary clinical indicators of infection due to immunosuppression. Immediate CBC and ANC testing are required to assess for life-threatening bone marrow suppression and neutropenia. Choice D reason: Scheduling a physical exam in two weeks is an inappropriate and dangerous delay in care. Agranulocytosis can progress rapidly to septicemia and death. Any patient on clozapine presenting with signs of infection must be evaluated immediately to ensure their safety and determine if medication cessation is necessary.