[Administration of levothyroxine in the treatment of Basedow disease]

Current therapy of Graves' disease is symptomatically effective in eliminating hyperthyroidism but is not directed towards the immunological cause of the disease. As a result, the majority of patients experience relapse of hyperthyroidism after antithyroid drugs have been discontinued and need to undergo radioiodine treatment or surgery. Improvement of efficacy of antithyroid drug therapy in inducing longlasting remission of Graves' disease has therefore been an elusive goal. A number of recent experimental and clinical trials have addressed the issue of improving and optimizing modalities of antithyroid therapy. In-vitro studies demonstrating direct immunosuppressive effects of thionamide drugs and encouraging results from a Japanese clinical trial suggested that maximum thyroid blockade and supplementation with levothyroxine might be effective in preventing relapse of disease. The superior efficacy of this approach could not be confirmed by others studies. On the other hand, these studies so far lack statistical power to prove a lack of effect of this approach. The issue of levothyroxine supplementation during antithyroid drug treatment should be separated from another issue of levothyroxine prophylaxis following successful treatment outcome. The latter question is currently addressed by a prospective randomized multicenter study.