Cardiac Tamponade in Procainamide Induced Lupus Erythematosus

After three years of procainamide 1.0 gram daily, a 56-year-old man presented with pleurisy and pleural effusion, which progressed to pericardial effusion and tamponade, requiring two pericardiocenteses within 24 hours. After four months of prednisone therapy, he was asymptomatic.