Diffuse alveolar damage in a patient receiving dronedarone.

Dronedarone is an amiodarone-like antiarrhythmic with a modified structure. The addition of a methyl sulfonyl group theoretically reduces the toxicity of amiodarone, specifically, adverse thyroid and pulmonary effects. Although animal studies have implicated dronedarone as a cause of lung injury, to date controlled trials in humans have not demonstrated an association. A 68-year-old woman developed a dry cough and worsening respiratory distress after receiving dronedarone for 6 months. Discontinuation of dronedarone therapy and subsequent steroid therapy led to a dramatic improvement of symptoms. Dronedarone may be associated with interstitial lung disease. We believe that patients receiving dronedarone should have their diffusing capacity of lung for carbon monoxide and lung volumes monitored prior to initiation of therapy and frequently thereafter.