Once daily, low dose, short term antithyroid drug treatment of Graves' disease is followed by an unacceptably high relapse rate.

Thirty-six patients with hyperthyroid Graves' disease were treated with low doses of antithyroid drugs until thyroid function test results indicated euthyroidism or mild hypothyroidism (median treatment period three months, range 1.5-8 months). Less than one-half (42%) of the patients remained hyperthyroid after two months of treatment, but 21% were still thyrotoxic after three months of treatment. Of 32 patients who completed treatment and entered the observation period after treatment was withdrawn, 27 (84%) have relapsed, two have remitted for one year or more and three have been followed for less than one year without relapse. Although once daily, low dose, short term antithyroid drug treatment of patients with Graves' disease in the Wellington area satisfactorily controls the hyperthyroidism in the majority of cases, it is followed by an unacceptably high relapse rate.