CLOZAPINE TREATMENT IN AUSTRALIA - A REVIEW OF HEMATOLOGICAL MONITORING

Background: Clozapine is an atypical antipsychotic drug indicated for patients with schizophrenia in whom traditional antipsychotic drugs (s uch as haloperidol or the phenothiazines) are ineffective, or in those who experience intolerable adverse effects. Clozapine treatment may b e complicated by the development of life-threatening agranulocytosis, so regular haematological monitoring is required. Objectives: To deter mine the incidence of clozapine-induced agranulocytosis in Australia a nd the importance of monitoring white blood cell counts in patients tr eated with clozapine. Design: Review of haematological monitoring for the first three years (June 1993 - July 1996) of operation of the Aust ralian Clozaril (clozapine; Novartis Australia) Patient Monitoring Sys tem (CPMS) central database. Results: In the 4061 patients prospective ly monitored by the CPMS, the incidence of agranulocytosis, neutropeni a and leukopenia combined was 2.6% (n=104); the incidence of agranuloc ytosis was 0.9% (n= 37). So far there have been no deaths in Australia from the complications of clozapine-induced agranulocytosis.Conclusio n: The incidence of agranulocytosis and neutropenia associated with cl ozapine use in Australia is similar to that in the rest of the world. Monitoring the white blood cell counts of patients being treated with clozapine ensures minimal risk to patients who develop agranulocytosis .