Clozapine-Induced Acute Pericarditis and Cardiac Tamponade: Early Recognition Improves Clinical Outcomes

Clozapine is approved for treatment-resistant schizophrenia. Many cardiovascular side effects are associated with clozapine, including QTc prolongation and myocarditis, which is a black box warning. Few cases of pericarditis have been reported in recent literature. We report a case of a 26-year-old male with schizoaffective disorder who presented with sharp chest pain and shortness of breath. The patient was started on clozapine three months prior to his current presentation. The workup revealed a large pericardial effusion with cardiac tamponade physiology and signs consistent with acute pericarditis. He required emergent pericardiocentesis and pericardial drain placement. Symptoms resolved after treatment with ibuprofen and colchicine. This case report highlights the importance of early diagnosis of life-threatening cardiovascular complications associated with clozapine, especially acute pericarditis and cardiac tamponade due to pericardial effusion. We strongly recommend implementing monitoring protocols to prevent this potentially life-threatening adverse effect in patients taking clozapine.