We describe four patients treated with lithium for the control of hyperthyroidism. Conventional therapy with propylthiouracil and/or methimazole was tried initially, but the patients were either unresponsive or developed side effects during the drug administration. Within several days of reaching therapeutic levels of lithium, a euthyroid state was achieved in three of the four cases. Our observations support the use of lithium as an alternative antithyroid drug in the treatment of hyperthyroidism in certain defined indications, a clinical use that is not widely known.
(C) 1998 Lippincott Williams & Wilkins, Inc.