[Drug-induced thyroid dysfunction].

Various drugs may cause thyroid dysfunction. The drugs which may cause thyrotoxicosis include interferon, molecular-targeted agents, amiodarone, thyroid hormone itself and so on. Those which cause hypothyroidism include anti-thyroid drugs, lithium and iodine etc. which inhibit thyroid hormone synthesis and secretion, and dopamine etc. which block TSH secretion. Those drugs which alter the thyroid hormone metabolism or the binding to TBG or those inhibit thyroid hormone absorption may cause hypothyroidism or deteriorate it in patients with hypothyroidism treated with thyroid hormone or those with diminished reserved capacity. When thyroid dysfunction occurred, it is better to discontinue the causative drug, but in many cases, the patients are forced to be treated with the drug being continued.