Clozapine-induced agranulocytosis and leukopenia: Incidence, associated factors, and rate of hematologic adverse-effects monitoring in psychiatric out-patient services in Thailand.

The present study aimed to investigate the incidence of agranulocytosis and leukopenia and its associated factors in Thai schizophrenia patients treated with clozapine and the rate of hematologic adverse events monitored in clinical practice. Data were collected from the medical records of 641 outpatients at two hospitals. The results showed no cases of agranulocytosis and 20 cases of leukopenia (3.1%), 85% of which were observed after 1 year of prescription. The associated factors were female (p = 0.019) and duration of clozapine prescription (p = 0.026). According to the guideline for safety monitoring, 23.6% of cases had neutrophils count monitoring.