Iodinated Contrast and Thyrotoxicosis

The risk of iodine-induced thyrotoxicosis is low in euthyroid patients, ranging from 0% to about 2.5% depending on the study. The risk for hyperthyroid patients has not been defined, but in one study of elderly hyperthyroid patients 25% developed self-limited hyperthyroidism after nonionic contrast radiography. Prophylactic medications may be given, and include perchlorate with or without thiamazole, but there are no studies on the benefits of these medications.

References

• Fricke E, Fricke H, Esdorn E, Kammeier A, Lindner O, Kleesiek K, Horstkotte D, Burchert W. Scintigraphy for risk stratification of iodine-induced thyrotoxicosis in patients receiving contrast agent for coronary angiography: a prospective study of patients with low thyrotropin. J Clin Endocrinol Metab. 2004 Dec;89(12):6092-6.
• Martin FI, Tress BW, Colman PG, Deam DR. Iodine-induced hyperthyroidism due to nonionic contrast radiography in the elderly. Am J Med. 1993 Jul;95(1):78-82.