The Jod-Basedow effect (also Jod-Basedow syndrome and Jod-Basedow phenomenon) is hyperthyroidism following administration of iodine or iodide,[1] either as a dietary supplement, for iodinated contrast medical imaging, or as a medication (mainly amiodarone).
The hyperthyroidism usually develops over 2 to 12 weeks following iodine administration.[2]
In some ways the Jod-Basedow phenomenon is the opposite of two physiological compensation mechanisms, the Plummer effect and the Wolff–Chaikoff effect, which in normal persons and in persons with thyroid disease, suppress the thyroid hormone after ingestion of large quantities of iodine or iodide. However, unlike the Plummer and Wolff-Chaikoff effects, the Jod-Basedow effect does not occur in persons with normal thyroid glands, as thyroid hormone synthesis and release in normal persons is controlled by pituitary TSH secretion, which does not allow hyperthyroidism when extra iodine is ingested.[citation needed]
The Jod-Basedow effect is named for the German word for iodine, Jod (all nouns are capitalized in German), plus the name of Karl Adolph von Basedow, a German physician who first described the effect. The nomenclature "Jod-Basedow" was carried over intact from German, rather than being translated.[citation needed]