Case Report: Early onset pulmonary embolism following antipsychotic polypharmacy in an acute psychiatric setting.

Pulmonary embolism (PE) is a potentially life-threatening condition that may occur in patients receiving antipsychotic medication. Several studies have shown an increased risk of venous thromboembolism (VTE) associated with the use of antipsychotics, particularly during the first weeks or months of treatment. However, very early onset of VTE within hours of treatment initiation has been rarely reported. We present the case of a 69-year-old woman who developed acute pulmonary embolism within a few hours after initiation of psychopharmacological treatment for a psychotic episode. Due to acute agitation, the patient received olanzapine, quetiapine, levomepromazine, and lorazepam. The patient had no known predisposing risk factors for VTE. Shortly after begin of psychopharmacological treatment she presented with deterioration of her general condition, soporous, hypotensive, tachycardic and with reduced oxygen saturation. PE was suspected clinically and confirmed by computed tomography pulmonary angiography. After diagnosis, PE was successfully treated with anticoagulation. This case is notable for the unusually rapid development of VTE, occurring within hours rather than the typically reported days to weeks. It underscores the need for heightened clinical vigilance even in the very early phase of antipsychotic therapy and in patients without risk factors for VTE.