What underlying condition is closely monitored in patients taking clozapine, due to its serious side effects?

Clozapine is an atypical antipsychotic that is particularly effective in treating treatment-resistant schizophrenia. One of the most significant risks associated with clozapine use is agranulocytosis, a potentially life-threatening condition characterized by dangerously low levels of neutrophils (white blood cells essential for fighting infections). This necessitates regular monitoring of the patient's white blood cell count, specifically the absolute neutrophil count (ANC), to ensure that bone marrow function is not compromised.

Because agranulocytosis can lead to severe infections and complications, healthcare providers must closely monitor bone marrow health in patients prescribed clozapine. This monitoring typically occurs through mandatory blood tests, especially during the initiation of treatment and for the duration of therapy, to mitigate the risks associated with this severe side effect. While other health aspects, such as cardiovascular health and liver and kidney function, are important, the primary concern with clozapine lies in its impact on bone marrow function.