Pulmonary embolism is a very serious, life threatening condition. It has been associated with the use of antipsychotic drugs, both typical and atypical, thus consisting a rare but potentially lethal side effect of this drug category. SSRIs/SNRIs on the other hand, are associated with bleeding, increased INR results and platelet dysfunction.

A clinical case was followed and reviewed to illustrate the possible connection between the withdrawal of duloxetine and the ongoing use of olanzapine with pulmonary embolism.

A 36-year- old male, smoker of 30 cigarettes/day had been under treatment with olanzapine 30 mg/day and aripiprazole 30 mg/day for the past year. Duloxetine 90 mg/day had also been added for the past nine months and withdrawn after the improvement of depressive symptoms. Approximately one month after its withdrawal the man suffered pulmonary embolism and was hospitalised. During hospitalisation tests found no other factors predisposing to emboli creation. He was discharged with acenocumarol (Sintrom). His psychiatric medication was therefore adjusted to omit olanzapine and SSRIs /SNRIs because of their potential effect on coagulation.

Can it be that olanzapine played a role in promoting pulmonary embolism in this patient ?

Can it be that duloxetine was playing a protective role and its withdrawal facilitated the onset of pulmonary embolism? There is no certain way to tell but, to our knowledge, there has not been a similar case before and the time sequence of the events might not be coincidental.