A client with schizophrenia has been started on medication therapy with clozapine. The nurse would assess the results of which laboratory study to monitor for adverse effect of this medication?

1. A

   Liver function studies

2. B

   Blood glucose level

3. C

   White blood cell count

4. D

   Platelet count

Appeared in: AIIMS Rishikesh & Jodhpur NO - 2017

Explanation

• Clozapine carries a black box warning for severe neutropenia (agranulocytosis), a potentially fatal drop in white blood cells.
• Agranulocytosis severely weakens the immune system, leaving the patient vulnerable to serious infections.
• Due to this risk, regular monitoring of the White Blood Cell (WBC) count and Absolute Neutrophil Count (ANC) is mandatory for all patients on clozapine.
• National registries exist to enforce this monitoring, often following a "no blood, no drug" policy to ensure patient safety.

Why Other Options Were Wrong

• Option A: While monitoring liver function is a good general practice, it is not the primary, life-threatening concern specific to clozapine. The risk of agranulocytosis is far more immediate and severe.
• Option B: Clozapine can cause metabolic changes, but the risk of agranulocytosis is the most critical and unique adverse effect requiring specific, frequent monitoring. Other antipsychotics, like olanzapine, have a higher risk for causing significant hyperglycemia.
• Option D: Clozapine's primary hematological toxicity affects the white blood cells (neutrophils), not platelets. A drop in platelets (thrombocytopenia) is not a characteristic adverse effect of this drug.

Related Visual

Clinical Relevance

• Nursing practice connection: Use the key finding related to Pharmacological monitoring for adverse effects of clozapine to guide bedside assessment, documentation, and the next nursing action.
• The nurse's role is critical in educating the patient and family about the signs and symptoms of infection (e.g., fever, sore throat, fatigue) and the importance of reporting them immediately.
• Nurses must ensure that the patient adheres to the strict blood monitoring schedule, as pharmacies will not dispense clozapine without current, acceptable lab results (the "no blood, no drug" policy).
• What if? If a patient on clozapine calls the clinic complaining of a fever and a sore throat, the nurse must instruct the patient to go to the nearest emergency department for an immediate STAT complete blood count (CBC) and to not take their next dose of clozapine until advised by a physician. This is a potential medical emergency.

How to Approach the Question

• First, identify the key medication in the question, which is 'clozapine'.
• Recall the major, unique, and life-threatening adverse effect associated with this specific drug. For clozapine, this is agranulocytosis.
• Connect the adverse effect (agranulocytosis) to the corresponding laboratory test. Agranulocytosis is a severe deficiency of white blood cells.
• Therefore, the necessary lab study is the 'White blood cell count' (and more specifically, the Absolute Neutrophil Count or ANC).
• Review the other options to confirm they are less critical. Liver function, blood glucose, and platelet count are important for other drugs or conditions but are not the primary safety concern for clozapine.

Concept Tested & Keywords

• Concept Tested: Pharmacological monitoring for adverse effects of clozapine
• Stem keywords: schizophrenia, clozapine, medication therapy, adverse effect, laboratory study
• Lead-in keywords: assess the results
• Clinical cues: Medication: clozapine

Question ID

Q5IzXB900qgowWUkz25uzb

Copy ID

Reference Book

E6 Robert Boland, Marcia L. Verduin - Kaplan and Sadock's Comprehensive Text of Psychiatry-Wolters Kluwer Health (2024) (pp 1-16525 of 16525) pp. 3488-3490, 9971-9973