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Potassium iodide Pregnancy and Breastfeeding Warnings

Potassium iodide is also known as: Iosat, Pima, SSKI, ThyroShield, Yodefan

Potassium iodide Pregnancy Warnings

Potassium iodide (KI) has been assigned to pregnancy category D by the FDA. KI can cause fetal harm, abnormal thyroid function and goiter when administered to a pregnant woman. Potassium iodide is considered contraindicated during pregnancy.

The use of KI, or any iodide, is contraindicated during pregnancy because of the potential for fetal goiter secondary to fetal thyroid trapping of iodide. There are data to suggest the safe use of short-term (10 days) of KI in preparation for maternal thyroidectomy. In 2001 the FDA issued a guidance document for the use of potassium iodide in radiation emergencies. The FDA stated pregnant women should be given should be potassium iodide for their own protection and for that of the fetus. However, because of the risk of blocking fetal thyroid function with excess stable iodine, repeat dosing of pregnant women should be avoided.

Potassium iodide Breastfeeding Warnings

In 2001 the FDA issued a guidance document for the use of potassium iodide (KI) in radiation emergencies. The FDA stated lactating women should be given should be potassium iodide for their own protection, as for other young adults, and potentially to reduce the radioiodine content of the breast milk, but not as a means to deliver KI to infants, who should get their KI directly. As for direct administration of KI, stable iodine as a component of breast milk may also pose a risk of hypothyroidism in nursing neonates. Therefore, repeat dosing with KI should be avoided in the lactating mother, except during continuing severe contamination. If repeat dosing of the mother is necessary, the nursing neonate should be monitored for the potential development of hypothyroidism.

Potassium iodide (KI) is excreted into and concentrated in human milk. While the American Academy of Pediatrics considers potassium iodide to be compatible with breast-feeding, many experts caution against the use of KI--or any iodide--during breast-feeding because of the risk of neonatal goiter and hypothyroidism. The effect of high concentration iodide ingestion on the nursing infant is not known.

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