Korean J Schizophr Res.  2019 Apr;22(1):1-7. 10.16946/kjsr.2019.22.1.1.

Prescribing Pattern of Clozapine and Clinical Factors associated with Discontinuation of Clozapine

• Kang SH
• Lee HW

• KMID: 2444215
• DOI: http://doi.org/10.16946/kjsr.2019.22.1.1

Abstract

OBJECTIVES
Clozapine is the drug of choice in treatment-resistant schizophrenia. However, its use is often delayed and a significant proportion of clozapine treated patients fails to respond and experience potentially dangerous side-effects. The aim of this retrospective study was to describe the clinical characteristics of patients started on clozapine and the rate and reason of discontinuation of clozapine.
METHODS
Medical records of 83 patients started on clozapine during the period of 2012-2016 were reviewed.
RESULTS
Clozapine started on patients in chronic phase; the mean age of start was 38.1 years old and the mean number of psychiatric admission was 6.5. A majority (80.7%) of the patients had been subjected to antipsychotic polypharmacy prior to clozapine and most (61.5%) of them were being treated with polypharmacy including clozapine. Overall, 39 (47.0%) subjects had continued clozapine whereas 15 (18.1%) discontinued it; 29 (34.9%) were lost to follow-up. The most common reason for discontinuation was side-effects (n=13) including six life-threatening cases, most of which occurred within 6 months of its start.
CONCLUSION
This study demonstrated that there is some evidence of delays to clozapine use, high rates of polypharmacy and significant rate of discontinuation during the early phase of clozapine treatment.

Keyword

Clozapine; Antipsychotics; Prescribing pattern; Discontinuation; Side effect

MeSH Terms

Antipsychotic Agents
Clozapine*
Humans
Lost to Follow-Up
Medical Records
Polypharmacy
Retrospective Studies
Schizophrenia
Antipsychotic Agents
Clozapine

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