Amiodarone and thyroid

Amiodarone, an iodine-rich drug, results in mild disturbances of thyroid function in most patients and in thyroid dysfunction in approximately 20% of them. Hypothyroidism, mainly found in countries without iodine deficiency, is substituted with levothyroxine and does not need amiodarone to be discontinued. Hyperthyroidism, commonly found in areas of iodine deficiency, is more complex and usually motivates discontinuation of amiodarone. Type I hyperthyroidism, induced by iodine overload, is treated with antithyroid drugs, and type 2, resulting from the cytotoxic effect of amiodarone, may be treated with glucocorticoids. Considering the risk of thyroid dysfunction in patients treated with amiodarone, it is recommended to check regularly TSH level.