Antipsychotic drugs and venous thromboembolism

Antipsychotic Drug Use and the Risk of Venous Thromboembolism in Elderly Patients

“…They did not find an association between antipsychotic drug use and deep vein thrombosis (DVT). In a surveillance program reported by Wolstein et al, 16 the difference in the incidence of VTE between users of clozapine (0.04%), users of other antipsychotic drugs (0.03%), and nonusers (0.03%) was not statistically significant. There is no published evidence to suggest a direct biologic mechanism.…”

Upper-Extremity Deep Vein Thrombosis in a Patient on Clozapine Therapy Carrying the Prothrombin G20210A Mutation

“…Regarding the incidence of venous thrombosis related to this drug, Hägg et al [4] reported, from the 12 cases of clozapine-associated venous thrombosis retrieved from the database of the Swedish Adverse Reaction Advisory Committee, that the risk of thromboembolism in clozapine-treated patients was at least 1 per 2,000-6,000. This figure was later confirmed by the 'Arzneimittelsicherheit' in the Psychiatric Project carried out in 35 psychiatric hospitals in Germany and Switzerland who found that the frequency of thromboembolism associated with clozapine treatment was 1 in 2,600 patients [5] .…”

“…The use of clozapine, an atypical antipsychotic agent for treating resistant chronic schizophrenia, has also been related to venous thromboembolism [4][5][6][7][8][9][10][11][12][13][14][15] , although the underlying prothrombotic mechanisms remain unknown. In the majority of reported cases, patients were not routinely screened for thrombophilia, so that the contribution of such genetic or acquired thrombophilic defects on the development of the thrombotic event cannot be ruled out.…”

Massive pulmonary embolism in a young patient on clozapine therapy

“…The mean clozapine dose was 277 mg/day (75-500 mg) (3). The estimated frequency of venous thromboembolism was 1 in 2000 -6000 treated patients (3,9). The mortality rate associated with pulmonary embolus was 1 death per …”

“…Several hypotheses have been proposed: antipsychotic drugs enhance aggregation of platelets or increase anticardiolipin antibodies, and venous stasis is exacerbated by sedation (3,7,8). However, the adverse effect of antipsychotic drugs may be an expression of some other underlying risk factor of the psychiatric disease itself, such as reduced motor activity during psychiatric treatment (2,9,10). The mechanism by which clozapine induces venous thrombosis should be studied.…”