Iodine-induced thyrotoxicosis in apparently normal thyroid glands.

Although iodine-induced thyrotoxicosis was reported to occur in patients with obvious underlying thyroid disorders, it is not known to occur in patients with apparently normal thyroid glands. From ten such cases evidence is presented that thyrotoxicosis: a) appeared during treatments by iodide or organic-iodine-containing drugs, in the absence of any past history of thyroid disorder; b) was accompanied by almost undetectable radioidine uptake which nevertheless could be activated by TSH; c) subsided spontaneously within a few weeks or months after stopping the high intake of iodine; d) and left, after a period of hypothyroidism, an apparently normal thyroid gland which had resumed normal size, function, uptake, and suppressibility.