Iodine in biology
The U.S. Institute of Medicine (IOM) updated Estimated Average Requirements (EARs) and Recommended Dietary Allowances (RDAs) for iodine in 2000. For people age 14 and up, the iodine RDA is 150 μg/day; the RDA for pregnant women is 220 μg/day and the RDA during lactation is 290 μg/day. For children 1–8 years, the RDA is 90 μg/day; for children 8–13 years, 130 μg/day. As a safety consideration, the IOM sets tolerable upper intake levels (ULs) for vitamins and minerals when evidence is sufficient. The UL for iodine for adults is 1,100 μg/day. This UL was assessed by analyzing the effect of supplementation on thyroid-stimulating hormone. Collectively, the EARs, RDAs, AIs and ULs are referred to as Dietary Reference Intakes (DRIs).
Iodine-123
Dosing can vary; is recommended for thyroid imaging while an uptake test may use . There is a study that indicates a given dose can effectively result in effects of an otherwise higher dose, due to impurities in the preparation. The dose of radioiodine I is typically tolerated by individuals who cannot tolerate contrast mediums containing larger doses of iodine such as used in CT scan, intravenous pyelogram (IVP) and similar imaging diagnostic procedures. Iodine is not an allergen.