Clozapine and Fluvoxamine Associated Pulmonary Embolism in Two Patients Without Known Risk Factors: A Case Report

Background: Pulmonary Embolism (PE) is a life‐threatening condition that has been associated with antipsychotic medications. The antipsychotic medication clozapine has had emerging evidence highlighting its association with the development of venous thromboembolism (VTE) in the absence of any other risk factors being present. Case Summary: We report two cases of severe bilateral PE in a 46‐year‐old and 49‐year‐old man receiving clozapine treatment and fluvoxamine augmentation for psychotic spectrum disorders. These patients had no pre‐existing risk factors for VTE and were at different stages of clozapine titration and treatment. Both patients made full cardiac and respiratory recovery despite the severity of their VTE and were treated with anticoagulant therapy. Conclusion: Clozapine is becoming increasingly recognized as an independent risk factor for VTE which can be a life‐threatening complication for patients. Diagnosing PE can be challenging due to the general cardiac side effects of clozapine, such as tachycardia and hypotension, highlighting the importance for psychiatrists to be vigilant in considering PE in their patients. Further evidence around the benefits of prophylaxis and risk stratification for VTE in patients on antipsychotic medications may further assist in the prevention of VTE in patients.