Radioactive Iodine Therapy

Also known as: radioiodine therapy, RAI

What is radioactive iodine therapy?

Radioactive iodine therapy, or radioiodine, is a treatment for hyperthyroidism and thyroid cancer. Among its other functions, the thyroid gland absorbs almost all iodine within the body. By introducing radioactive iodine, the idea is that it will destroy thyroid cells, including cancerous cells, without impacting the rest of the body.

What happens during the treatment?

Radioactive iodine therapy is administered in oral capsule form. It usually does not require hospitalization. In the case of thyroid cancer, radioactive iodine is typically given after a surgery to remove the thyroid gland to destroy any remaining cancerous thyroid tissue. The dose given for thyroid cancer is much higher than it is for hyperthyroidism.

Is any special preparation needed?

A diet low in iodine will be ordered before the therapy for the radioactive iodine to work. Patients will need to drink lots of water to flush their system of radioactive iodine. They will also need to avoid contact and maintain their distance from all others for several days to avoid radiation exposure. Patients should also avoid sharing kitchen utensils and clean and launder items separately from others. Talk to your health care provider for more specific instructions.

What are the risk factors?

Neck tenderness and swelling, nausea, loss of taste or taste change, dry mouth and eyes or excessive tearing from the eyes are all temporary side effects of radioactive iodine therapy.


Reviewed by: Alejandro Diaz, MD

This page was last updated on: June 29, 2022 01:35 PM

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