Charles Armstrong

COBALT ADMINISTRATION AND THYROID ACTIVITY

To the Editor:— As stated in an editorial inThe Journal, Aug. 13, page 1371, a difference of opinion has arisen with regard to the effect of therapeutic doses of cobaltous chloride upon thyroid function. I have recently been privileged to observe 10 members of an Italian family, 6 of whom have the hereditary leptocytosis trait to a greater or lesser degree. Each of these patients was given cobaltous chloride in dosages ranging from 25 to 100 mg. per day in the case of two children, aged 5 and 11; and 25 to 125 mg. per day in the instance of three adults, aged 26, 28, and 54. Experimental supplies of cobaltous chloride, furnished in 25-mg. enseals, were used during this study. Gastric irritation accompanied by vomiting was exceedingly common. In every instance, the anemia was improved during the period of cobalt administration. Iron was not given concomitantly. In several