LONG-TERM CONTROL OF THYROTOXICOSIS WITH THE BETA-BLOCKER SOTALOL - A MODEL OF UNTREATED HYPERTHYROIDISM?

Abstract

ABSTRACT Five patients with hyperthyroidism and no goitre were treated only by beta blockade with sotalol. All but one became clinically euthyroid, although the thyroid hormone values in their sera remained high. The TSH response to intravenous TRH remained absent. One patient had fluctuating thyroid hormone values, one has had borderline values for 20 months, one had a hormonal recovery within 6 months, one became clinically thyrotoxic and was switched to carbimazole, and one who had first been treated with carbimazole and had a relapse of high hormone values at 3 months and of clinical symptoms within 9 months after cessation of carbimazole treatment became clinically euthyroid with beta blockade. Sotalol offers a symptom control of hyperthyroidism without lowering the thyroid function, and thus makes it possible to study the long-term hormonal pattern of hyperthyroidism without suppression of thyroid hormone secretion. The results show that the course of hyperthyroidism may vary in duration and pattern. TRH stimulation may cause none or a small TSH response even when the disease is in hormonal remission. The cause of this phenomenon is discussed. The duration of hyperthyroidism cannot be forecast by present methods, and this should be borne in mind when patients are treated with antithyroid drugs for this disorder.