LACK OF EFFECT OF FLUOXETINE ON THE HYPOPROTHROMBINEMIC RESPONSE OF WARFARIN

The purpose of this study was to assess the effect of fluoxetine on th e hypoprothrombinemic response of warfarin in patients chronically ant icoagulated. Patients receiving low-intensity anticoagulation with war farin were recruited, All patients were taking stable dosages of warfa rin and had two baseline prothrombin times (PTs) within 10% of each ot her. Each patient received fluoxetine (20 mg daily) for 21 days. PTs w ere measured on days 2, 5, 8, 12, 15, 19, and 22 of fluoxetine adminis tration. Six patients completed the study. There was no significant di fference in mean PTs before and during fluoxetine administration. Fluo xetine at the dosage studied does not predictably effect the hypoproth rombinemic response of warfarin.