The Effects of L-Thyroxine Sodium on Nontoxic Goiter, on Myxedema and on the Thyroid Uptake of Radioactive Iodine

SYNTHETIC thyroxine is apparently absorbed and physiologically active when ingested, although it has generally been used intravenously.1 2 3 4 5 6 Clinical studies employing oral administration of 1-thyroxine sodium have demonstrated its effectiveness in treating and maintaining athyreotic patients.5 , 6 The possible advantages inherent in a therapeutic agent of constant potency and composition have prompted further clinical evaluation of 1-thyroxine sodium in patients with myxedema. In addition, we have studied the suppressive effect of 1-thyroxine administration on the thyroid uptake of radioactive iodine, as well as its influence on the size of nontoxic goiters.MethodsUptakes of radioactive iodine were determined in 7 patients with . . .