A Slow, Cautious, and Successful Clozapine Rechallenge After Myocarditis

• Type of Material: Article
• Authors: Philip Bowers, Emory University; Bradley Rosenkrantz, Emory University; Justin Palanci, Emory University; David Goldsmith, Emory University; Robert Cotes, Emory University
• Language: English
• Date: 2022-01-01
• Publisher: Emory University Libraries
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © Copyright 2022 Physicians Postgraduate Press, Inc.
• Final Published Version (URL): http://dx.doi.org/10.4088/PCC.21cr02976
• Title of Journal or Parent Work: Primary Care Companion for CNS Disorders
• Volume: 24
• Issue: 2
• Keywords: Myocarditis; Antipsychotic Agents; Clozapine; Humans; Schizophrenia

Abstract

United States guidelines recommend clozapine for the treatment of schizophrenia when an individual has inadequate response to 2 adequately dosed antipsychotic trials.1 Despite superior efficacy,2,3 prescriber concern for life-threatening effects is one of the main drivers for its underutilization.4 Clozapine-induced myocarditis (CIM) is one such life-threatening event, occurring in 0.7% of people exposed to clozapine, most commonly within the first month of clozapine titration.5,6 Notably, incidence appears to be higher in Australia (2%) compared to the rest of the world (0.3%), possibly due to increased echocardiographic screening in Australia after the year 2000.6,7 Myocarditis screening protocols, which commonly include close monitoring for clinical signs and symptoms, vital sign monitoring, and laboratory tests including C-reactive protein (CRP) and troponin I/T, may facilitate the early identification of clozapine-induced myocarditis.8 However, if an individual develops CIM, clinicians face the dilemma of whether to rechallenge with clozapine, especially since many individuals have not adequately responded to other antipsychotic medications and are actively experiencing impairing symptoms. We present a case of an otherwise healthy 23-year-old man with schizophrenia who was successfully rechallenged with clozapine after developing myocarditis.