Radioiodine therapy for Graves' disease: Case selection and restrictions recommended to patients in North America

Each of the three major therapies for Graves' disease has its own advantages, disadvantages, indications, and contraindications. Today, radioactive iodine (RAI) therapy is the most commonly employed means of therapy for Graves' disease in the United States, with approximately 70% of patients so treated after initial presentation and an additional fraction of arguably 10-15% treated with RAI after failure of antithyroid drugs or surgery. RAI therapy is acknowledged to have the clear-cut advantage of being safe, with very low morbidity and cost. The indications for RAI therapy are clear and noncontroversial for most patients with Graves' disease. Moreover RAI treatment is employed by some thyroidologists for subclinical thyrotoxicosis (normal T-4 or T-3 but immeasurable TSH), particularly in patients > age 45 due to risks of atrial fibrillation. RAI therapy is not considered indicated or is contraindicated during breast feeding and in pregnancy, subacute thyroiditis, postpartum thyroiditis, struma ovarii, pituitary (TSH-driven) hyperthyroidism, euthyroid hyperthyroxinemia, and thyroid hormone resistance. Opinions vary on the use of RAI therapy in children with Craves' disease; generally, a lower age cutoff of 17 years is acceptable in most clinics. Even more controversial is whether RAI therapy in the presence of Graves' ophthalmopathy constitutes a risk for worsening ophthalmopathy. Resolution of this latter issue awaits more definitive studies, but RAI therapy is likely to remain the first choice for most patients with Graves' disease.