Does Concomitant Amiodarone Use Increase Bleeding Risk with Apixaban or Rivaroxaban?

Currently, two direct factor Xa inhibitors, apixaban and rivaroxaban, are the leading anticoagulants used to reduce the risk for stroke among people with atrial fibrillation. The anticoagulant activity of these drugs is related to the plasma concentration. Amiodarone, a commonly prescribed rhythm control medication for patients with atrial fibrillation, inhibits the mechanisms that eliminate apixaban or rivaroxaban from the body and increases blood concentration. However, the FDA labels for these drugs do not indicate an increased bleeding risk with concomitant amiodarone use.

In a retrospective study, investigators used Medicare data to examine whether amiodarone is associated with an increased bleeding risk when used with apixaban or rivar…