Some patients need oral anticoagulant treatment to prevent a thromboembolic event (pulmonary embolism, etc.). Warfarin is the most thoroughly evaluated oral anticoagulant, but despite that fluindione is the oral anticoagulant most frequently prescribed in France.
In addition to bleeding effects specific to oral anticoagulant, fluindione also causes unpredictable and sometimes severe immunoallergic adverse effects.
Around 100 adverse effects have been reported in just one year in France, and several hundred reports have been analysed. Often several organs are affected, especially the skin, liver and kidneys, frequently accompanied by fever. Several dozen severe cases have been reported.
Clinical presentation, the lesions themselves and the chronology of events often suggest an immunoallergic mechanism. These adverse effects generally clear up quickly on halting the drug. However, in some instances, the lesions persist sometimes for several months. Resuming treatment with fluindione exposes the patient to a severe recurrence.
When an oral anticoagulant is necessary, it is preferable to choose warfarin initially. For patients already taking fluindione, close monitoring is essential.
©Prescrire November 2010
"Immunoallergic adverse effects of fluindione" Prescrire Int 2010; 19 (110): 255-256 (Pdf, subscribers only).