Clozapine prescribing in a Canadian outpatient population.

Objective Description of demographics of an outpatient population of clozapine users. Methods Retrospective chart review study of an urban population diagnosed with schizophrenia. Assessment of therapeutic histories in relation to clinical practice guidelines. Results Seventy-seven of the 467 patients were on clozapine therapy. Average patients’ age was 39.4 ± 11.8 years) and 68% were males. The majority of patients (68%) had tried 3 or more antipsychotics before switching to clozapine, 21% had tried two and 11% had tried one. Median length of therapy prior to clozapine initiation was 8.9 years in males and 7.7 years in females. Conclusion Until 2010, the use of clozapine was often delayed and more than 2 antipsychotic medications were tried for relatively long periods of time before patients were switched to this effective agent.