Thyroidectomy for amiodarone-induced thyrotoxicosis

Abstract

Amiodarone hydrochloride, an iodine-rich drug used in the treatment of tachyarrhythmias, is responsible for the development of thyrotoxicosis in approximately 10% of patients who reside in areas of moderate iodine deficiency. Treatment of amiodarone-induced thyrotoxicosis is difficult since the drug has a prolonged half-life, cardiac decompensation due to underlying heart disease occurs often, and discontinuation of amiodarone therapy may not be possible. We report a patient with severe thyrotoxicosis who received amiodarone for 34 months. Prolonged treatment with methimazole, potassium perchlorate, iopanoic acid, and dexamethasone was unsuccessful in controlling the hyperthyroid state. A near-total thyroidectomy resulted in rapid amelioration of thyrotoxicosis. Since surgery results in rapid control of thyrotoxicosis and permits continued therapy with amiodarone, we suggest that near-total thyroidectomy warrants consideration as definitive treatment for resistant amiodarone-induced thyrotoxicosis.