Thionamide Therapy in Graves' Disease: Relation of Relapse Rate to Duration of Therapy

Abstract

The present study was undertaken to investigate whether there is a rational basis for the usual long periods of thionamide therapy in patients with hyperthyroid Graves'' disease. Untreated patients (80) were given the minimum dose of thionamide drug needed to maintain serum thyroxine, triiodothyronine and thyrotropin (TSH) concentrations within their normal ranges. Thyrotropin-releasing hormone (TRH) tests were done at 6 monthly intervals for 2 yr. Among patients who had positive responses of TSH to TRH, approximately 10 patients every 6 mo. were asked to stop thionamide therapy and were followed up for at least 1 yr after discontinuation of drugs. In the groups treated for 6, 12, 18 and 24 mo., relapses occurred in 9 of 13, 5 of 9, 3 of 12, and 2 of 11 patients, respectively. Values for thyroid function tests before and at the end of treatment were not different among these 4 groups of patients. The overall remission rates were not ascertained. However, a minimum of 1 yr treatment is recommended.