Abstract
Although new oral anticoagulants are known to have decreased bleeding risk compared to vitamin K antagonists, they may cause major bleeding in rare cases. In this article, we report a 78-year-old female patient who developed spontaneous hemothorax after rivaroxaban use. Left-sided pleuritic chest pain occurred in the patient due to the rivaroxaban she received for pulmonary thromboembolism. Diagnostic thoracentesis revealed a grossly bloody pleural effusion. Rivaroxaban was discontinued and the drainage of the hemothorax was performed by fine needle aspiration. To our knowledge, this is the first case report of rivaroxaban-induced spontaneous hemothorax, drawing attention to major hemorrhagic complications of new oral anticoagulants.