Antipsychotic drugs linked to venous thrombosis

The use of antipsychotic drugs appears to be a risk factor for venous thrombosis (VT), according to a new report from the Netherlands.

The researchers reviewed the autopsy reports of 10 psychiatric patients who had died of idiopathic pulmonary emboli (clots in the pulmonary artery of unknown origin). They then carried out a literature review of venous thrombosis in psychiatric patients, and reanalysed data from a case control study of patients with deep vein thromboses (DVTs).

It was found that half the autopsied patients had used antipsychotic drugs, and the literature review identified several German studies that had found a higher incidence of VTs in psychiatric patients after the introduction of chlorpromazine and related type drugs.

Reanalysis of the case control study revealed that, while none of the 474 control subjects used antipsychotics, four of the 474 patients with DVTs did.

The association between VTs and antipsychotic medication is not well researched and the risk appears to be low. Nevertheless, more study is needed to understand how antipsychotic use can lead to increased VT risk (Br J Psychiatry, 2001; 179: 63-6).