Olanzapine: a new risk factor for pulmonary embolus?

Pulmonary embolus (PE) is not an uncommon cause of sudden death, and forensic pathologists are not unaccustomed to being the first to diagnose a PE in a patient, since they are often fatal. Forensic pathologists are also familiar with the known risk factors for development of PEs, including advanced age, use of oral contraceptives, smoking, obesity, a sedimentary lifestyle, postsurgery or postinjury, pregnancy, certain malignancies, factor V Leiden and prothrombin mutations, and anticardiolipin antibodies. It has recently been shown in the clinical literature that antipsychotic medications are associated with an increased risk of thromboembolic events. Clozapine, a close relative of olanzapine, has been implicated as an independent risk factor for developing a PE. Four cases have been published within the last 2 years questioning whether olanzapine may also be associated with an increased risk for PE. We report 6 cases from the Bexar County Medical Examiner's Office, occurring between 1998 and 2005 where olanzapine may have been a risk factor in the development of, and death from, PE.