IPODATE THERAPY IN PATIENTS WITH SEVERE DESTRUCTION-INDUCED THYROTOXICOSIS

We describe 4 patients with severe destruction-induced thyrotoxicosis who had a rapid clinical response to oral sodium ipodate (500 mg daily ), The underlying thyroid disorders in the patients were postpartum th yroiditis, subacute thyroiditis, silent thyroiditis, and radiation-ind uced thyroiditis. Ipodate therapy was given for 6 to 10 weeks until re storation of thyroid function to normal, In all patients, an almost co mplete resolution of symptoms occurred by the third day of ipodate tre atment. In the patient with radiation thyroiditis, a daily clinical sc ore of thyrotoxicosis declined within 2 to 3 days. The score remained low as long as the patient was receiving ipodate, but 2 attempts to di scontinue ipodate therapy while thyroxine levels were elevated resulte d in a rise of the thyrotoxicosis clinical score. This suggests that i podate therapy, by rapidly reducing triiodothyronine levels through in hibition of the 5' monodeiodination and blockage of the peripheral eff ects of thyroid hormone, controls severe thyrotoxicosis mediated by de struction and should be considered in this setting in conjunction with beta-adrenergic blockade.