Four cases of venous thromboembolism associated with olanzapine.

Aims: Psychiatric disorders and treatment with conventional antipsychotic medications have been associated with venous thromboembolism, but only a few data on recent antipsychotics such as olanzapine are available.

Methods: We describe four subjects treated with olanzapine who developed venous thromboembolism, and were hospitalized at the University Hospital in Hradec Kralove during the period 2004-2006.

Results: We found a combination of several clinical and laboratory risk factors in our patients.

Conclusions: A cohort study or case-control studies are needed to better elucidate the possible role of olanzapine in etiopathogenesis of venous thromboembolism.