An unusual complication of a long-acting injectable antipsychotic: deep venous thrombosis caused by olanzapine pamoate

Antipsychotic drugs are widely used in psychiatry and are associated with an increased risk of adverse effects such as venous thromboembolism. Olanzapine pamoate is a long-acting injectable form of the second-generation antipsychotic agent. It is used especially in schizophrenia patients who are nonadherent to their prescription due to various reasons. Since the introduction of this newer depot form of olanzapine, it became more commonly prescribed and nearly replaced the conventional oral agent. Deep venous thrombosis (DVT) is a severe, life-threatening condition which is somehow mostly underestimated or ignored by the psychiatrists. Although the risk of DVT due to antipsychotic drug therapy has been mentioned in various studies, the relationship with olanzapine pamoate was not referred to in the available literature. Here, a DVT after the use of olanzapine pamoate was introduced.