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Sodium iodide-i-131 Pregnancy and Breastfeeding Warnings

Sodium iodide-i-131 is also known as: Hicon, Iodotope

Sodium iodide-i-131 Pregnancy Warnings

Sodium iodide-I-131 has been assigned to pregnancy category X by the FDA. Sodium iodide-I-131 is contraindicated in women who are or may become pregnant. Sodium iodide-I-131 readily crosses the placenta. The fetal thyroid is able to accumulate I-131 until after about 10 to 12 weeks of gestation. Therapeutic doses of sodium iodide-I-131 administered near the end of the first trimester (12 weeks or beyond) usually result in partial or complete abolition of the fetal thyroid. Patients treated with sodium iodide-I-131 should be advised to delay conception for at least six months after treatment. Animal reproduction studies have not been conducted with sodium iodide-I-131.

Sodium iodide-i-131 Breastfeeding Warnings

Sodium iodide-I-131 is concentrated in breast milk. Because exposure to radioactive iodine may result in damage to the nursing infants thyroid, including an increased risk of thyroid cancer, breast-feeding should be stopped until radioactivity is no longer present in breast milk.

References for breastfeeding information

  1. Saha GB. "Fundamentals of Nuclear Pharmacy. 4th ed." New York, NY: Springer-Verlag (1998):

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