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Radioiodine in the treatment of hyperthyroidism

Douglas S Ross, MD
Section Editor
David S Cooper, MD
Deputy Editor
Jean E Mulder, MD


Radioiodine is widely used for the treatment of Graves' hyperthyroidism. It has been the therapy of choice in the United States, selected by 60 percent of thyroid specialists who responded to a survey in 2011 but only 13 percent of European thyroid specialists [1]. Low rates of use were also reported in surveys in the United Kingdom and Australia [2,3].

Radioiodine is administered orally as sodium iodide (131-I) in solution or a capsule. The radioiodine is rapidly incorporated into the thyroid, and its beta emissions result in extensive local tissue damage. The net effect is ablation of thyroid function over a period of 6 to 18 weeks.

Radioiodine for the treatment of hyperthyroidism will be reviewed here. Other treatment options for Graves' hyperthyroidism and toxic adenoma and toxic multinodular goiter (MNG) are reviewed separately. (See "Graves' hyperthyroidism in nonpregnant adults: Overview of treatment" and "Treatment of toxic adenoma and toxic multinodular goiter".)


Graves' disease — The therapeutic approach to Graves' hyperthyroidism consists of both rapid amelioration of symptoms with a beta blocker and measures aimed at decreasing thyroid hormone synthesis with either the administration of a thionamide, radioiodine ablation, or surgery [4]. Because all three treatment modalities are effective, the choice of therapy should involve active discussion between clinician and patient (table 1).

Radioiodine has been the most popular treatment for hyperthyroidism in the United States, although use of thionamides may be increasing [5]. Radioiodine is less popular outside of the United States [1-3,6]. The choice of therapy for Graves' disease is reviewed separately. (See "Graves' hyperthyroidism in nonpregnant adults: Overview of treatment", section on 'Choice of therapy'.)

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Literature review current through: Nov 2017. | This topic last updated: Jan 27, 2017.
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