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Radioactive iodine (RAI) is often chosen for treatment of hyperthyroidism (overactive thyroid) because of its simplicity: it is given in a single dose. Another plus for RAI is its lack of side effects.

Precautions

Some precautions are necessary because of the small amount of radiation that emanates from the neck where the RAI is stored for a few days after treatment. While this radiation is beneficial for the person being treated, precautions are needed to reduce the radiation families and friends are exposed to.

1. Avoid prolonged contact with others, especially children and pregnant women.

In general, a distance of one arm's length should be maintained between the person treated and others who spend more than two hours next to the patient in any 24 hour period. This applies especially to children and pregnant women. While brief contact with a person after treatment is acceptable, sleeping together, watching television, going to movies, long care or plane trips should be avoided for approximately 11 days after the treatment.

http://www.endocrinologist.com/Radioactive.html

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