Clozapine-Induced Myocarditis: A Systematic Review of Case Reports

Clozapine-Induced Myocarditis (CIM) is a rare but potentially life-threatening adverse drug reaction linked with the use of clozapine in treatment-resistant. The aim of this systematic review is to recognise the clinical features, diagnostic findings, and clozapine rechallenge outcomes. A systematic literature search was carried out according to the PRISMA 2020 guidelines using PubMed, Scopus, Web of Science and Google Scholar. Case reports published within the past 10 years were screened, and the following data were extracted: demographic details, clinical presentation, diagnostic findings, and outcomes. Using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist, the quality of included case reports was evaluated. Within the first 2 to 4 weeks of clozapine administration, myocarditis development was reported. The most common clinical symptoms included sinus tachycardia, fever, chest pain, and flu-like symptoms. Elevated cardiac troponins and inflammatory markers were the most dependable diagnostic findings, rather than electrocardiographic and echocardiographic, as they were variable. The primary management approach was sudden discontinuation of clozapine and cardiac supportive care. Clozapine rechallenge was attempted in selective cases with critical monitoring but had outcome variations. Clozapine-induced myocarditis is a rare but fatal adverse drug reaction which requires immediate recognition. Timely discontinuation of clozapine and supportive management are important for suitable outcomes. Standard monitoring protocol and more research in predictive biomarkers are critical to improve patient safety and early recognition.