A retrospective study on clozapine-induced blood dyscrasias in the first 20 weeks of therapy.

OBJECTIVE

Clozapine (CZP) is not commonly prescribed mainly because of the risk of serious adverse effects, particularly neutropenia. It can also cause blood disorders, ranging from mild to severe, affecting different blood cell types. The aim of this study was to investigate the incidence of hematological abnormalities in a Pakistani cohort of patients treated with antipsychotics using a comprehensive hematological monitoring program.

METHODS

The study included 288 patients categorized into three clinical groups based on antipsychotic treatment: Group TA (typical antipsychotics), Group AA (atypical antipsychotics), and Group CZP. During the initial 20-week treatment period, patients were regularly monitored hematological to assess changes in their blood profiles. The occurrence of various hematological abnormalities was investigated and analyzed using statistical models.

RESULTS

Blood dyscrasias were observed more frequently in patients in the CZP group than in the other groups. Specifically, neutropenia was seen in a few patients in group CZP. Notably, a positive clinical response to CZP treatment was significantly correlated with transient leukocytosis, transient neutrophilia, and persistent anemia. In contrast, poor clinical response to CZP medication was associated with transient leukopenia.

CONCLUSION

CZP treatment resulted in more blood disorders than TA or AA treatments. While blood abnormalities were common with CZP, severe neutropenia was rare. Certain blood changes were linked to better treatment outcomes. Therefore, regular blood monitoring is recommended to optimize treatment effectiveness and manage side effects.