Olanzapine and pulmonary embolism, a rare association: a case report

Venous thromboembolism is a very common pathological process for which there are many well known (and less well-known) predisposing factors. Likewise, olanzapine is a commonly used anti-psychotic medication. We present the case of a young Somali gentleman who developed venous thromboembolic disease after an overdose of olanzapine. The diagnosis was only made 48 hours after admission, due to the non-specific presentation of the pulmonary embolus and the fact that the link between olanzapine and pulmonary embolus was not previously widely described and therefore it did not immediately figure in the differential diagnosis. The patient made a full recovery. There is an increasing body of circumstantial evidence linking olanzapine to pulmonary embolus. Clinicians should bear this possible association in mind when prescribing the drug and when faced with clinical situations where venous thromboembolism (VTE) is a possible diagnosis. VTE has occasionally been described in therapeutic dose olanzapine therapy, but never in the context of an acute overdose. Khat, a recreational drug, has been linked to arterial, but not venous thrombosis. It is hoped that this case report will further encourage research into these associations, which remain to be proven and quantified. In the context of changing population demographics and increasing global migration, a greater awareness of the potential effects of endemic practices and their potential consequences is essential to the modern-day doctor working in a multi-cultural society.