It is accepted practice to give smaller than standard dosages of digitalis to patients with hypothyroid disease and larger ones to those with hyperthyroidism. The clinician can defend this approach by referring to a number of studies which confirm the necessity to administer larger amounts of digitalis to control atrial fibrillation in thyrotoxic patients than in those with myxedema. Is there, however, an objective basis for such usage in the absence of atrial fibrillation?
Basic to our understanding of digitalis bodies in thyroid disease is an evaluation of the serum levels, turnover rates, and excretion in patients with thyroid dysfunction as compared to subjects in the euthyroid state. Doherty and Perkins1 have recently reported the results of such a study. Tritiumlabeled digoxin was administered to 19 patients with thyroid disease, and the results were compared to those obtained in 25 euthyroid patients with congestive heart failure who received this