[Hyperthyroidism induced by iodinated roentgen contrast media].

Three patients with subclinical hyperthyroid goitre, women aged 63, 72 and 75 years following intravenous administration of an iodinated contrast medium developed hyperthyroidism with a marked rise of the concentration of free T4. Thyreostatic agents were unsuccessful in two patients, the third was left untreated. Hyperthyroidism improved spontaneously in all three. Iodine-induced hyperthyroidism is rare and is usually encountered in patients with a pre-existent autonomous thyroid function. Treatment of iodine-induced hyperthyroidism is essentially exclusively symptomatic. Prophylaxis with sodium perchlorate should be considered in cardiac patients with a goitre and a subnormal level of thyroid-stimulating hormone (TSH).