Recently we1 presented our findings concerning the normal urinary iodine of man, together with a review of the pertinent literature. At present few data2 concerning the urinary loss of iodine in hyperthyroidism are available. These reveal a pathologic increase in the urinary excretion of iodine in certain patients with hyperthyroidism. We therefore became interested in making a more extensive investigation of this particular problem in order to determine significant variations from normal in the daily urinary loss of iodine of hyperthyroid patients.
Phillips and one of us (G. M. C.)2a observed in 1932 an increased urinary loss of iodine during certain phases of hyperthyroidism. Since that time others3 have reported their investigations on patients with hyperthyroidism. The latter findings, on the whole, confirm the earlier ones.2a,b Our purpose in the present communication is to report an extensive investigation of the renal excretion of iodine of forty