Comparison of Radioiodine with Radioiodine plus Lithium in the Treatment of Graves ’ Hyperthyroidism*

Effectiveness of radioiodine for Graves ’ hyperthyroidism depends also on its intrathyroidal persistence. The latter is enhanced by lith-ium by blocking iodine release from the thyroid. One hundred ten patients with Graves ’ hyperthyroidism were randomly assigned to treatment with radioiodine or radioiodine plus lithium, stratified according to goiter size (#40 or.40 mL) and evaluated for changes in thyroid function and goiter size, at monthly intervals, for 12 months. Cure of hyperthyroidism occurred in 33 of 46 patients (72%) treated with radioiodine and in 45 of 54 patients (83%) treated with radio-iodine plus lithium. The probability of curing hyperthyroidism was higher and its control prompter (P 5 0.02) in the radioiodine-plus-lithium group. Patients with #40-mL goiters had similar persistence of hyperthyroidism (13%), but lithium-treated patients had hyper