In patients treated with clozapine, which symptom cluster should prompt medical evaluation?

• A. Headache and dizziness
• B. Fever, sore throat, chills, and malaise
• C. Nausea and vomiting
• D. Rash and photosensitivity

Answer: (B)

When a patient is on clozapine, fever accompanied by sore throat, chills, and malaise signals a possible drop in neutrophils, i.e., neutropenia or agranulocytosis. This is a potentially life-threatening reduction in the white cells that fight infection, so it requires urgent medical evaluation. The clinician will typically order a complete blood count with differential to check the neutrophil count and assess the infection risk, and they may pause clozapine until counts recover. This is why that symptom cluster is prioritized: it directly points to a serious hematologic adverse effect unique to clozapine that needs prompt action. Other symptoms like headaches with dizziness, nausea/vomiting, or rash alone are less specific for neutropenia and do not carry the same immediate risk signal, though they may occur with various drug effects. Regular WBC/ANC monitoring is essential with clozapine to catch neutropenia early and prevent complications.