It has been reported1that sodium dextrothyroxine (Dextroid) can reduce the serum cholesterol concentration in myxedematous patients in a dosage which does not raise the basal metabolic rate or potentiate the electrocardiogram. Other studies2indicate that this drug lowers the serum cholesterol level in euthyroid idiopathic and diabetic hypercholesteremic patients. Such effects might be due to the admixture of a small percentage of the levoisomer in the large amount of dextroisomer used in these patients, but the following case report makes this seem unlikely. Report of a Case A 64-year-old woman had a total thyroidectomy in 1951 which resulted in athyreosis, indicated by a serum protein-bound iodine level of 1.6 mcg.% and a 3% increase in radioactive iodine uptake after the administration of thyroid-stimulating hormone. Relief of myxedema was attempted, but the development of angina pectoris during the administration of desiccated thyroid necessitated a decrease in the dosage.