Clozapine for refractory schizophrenia: the Illinois experience.

Based upon the Illinois Department of Mental Health and Developmental Disabilities' computerized clinical information system, with its integration of client-specific clinical data, a 5-year retrospective study was designed to determine the clinical effectiveness and economic impact of the use of clozapine for treatment-resistant schizophrenia. The study sample consisted of 518 hospitalized, treatment-resistant patients. At the end of 5 years, 78% were well maintained on clozapine. Two hundred forty-three patients had been discharged to the community, and 62 had been transferred for treatment of medical or surgical problems. Clozapine treatment was discontinued in 115 patients (22%). The drug was well tolerated, with a very low incidence of agranulocytosis. Cost savings resulting from the discharge of the 243 clozapine-treated patients amounts to approximately $20 million per year. A disease management algorithm has been developed allowing physicians to begin clozapine treatment for patients not successfully treated with 2 prior antipsychotic agents. Adherence to this protocol throughout the state's mental health system would result in even greater savings.