sodium iodide I 131, Iodotope, Sodium Iodide I 131 Therapeutic

  • Pharmacy Author:
    Omudhome Ogbru, PharmD

    Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.

  • Medical and Pharmacy Editor: Jay W. Marks, MD
    Jay W. Marks, MD

    Jay W. Marks, MD

    Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

What is sodium iodide I 131, and how does it work (mechanism of action)?

Sodium iodide I 131 is an oral medication used to treat hyperthyroidism (overactive thyroid gland) and some cases of thyroid cancer. It falls under the category of an anti-thyroid drug but differs from the other anti-thyroid drugs, propylthiouracil (PTU) and methimazole (Tapazole), because it is radioactive. Sodium iodide I 131 is taken by mouth, readily absorbed into the body and is trapped within the thyroid gland. The trapped sodium iodide I 131 irradiates the thyroid gland thereby damaging it. As a result, the activity of the thyroid gland (that is, the production and release of thyroid hormone) is reduced. Excess sodium iodide I 131 is eliminated from the body in the urine by the kidneys. The sodium iodide retained in the body loses most of its radioactivity over several weeks. The half-life of the radioactivity is eight days. The FDA approved sodium iodide I 131 in August 1971.

What brand names are available for sodium iodide I 131?

Sodium Iodide I 131 Therapeutic, Hicon

Is sodium iodide I 131 available as a generic drug?

GENERIC AVAILABLE: Yes

Do I need a prescription for sodium iodide I 131?

Yes

What are the side effects of sodium iodide I 131?

The side effects commonly seen with sodium iodide I 131 treatment are mild with the smaller doses given for hyperthyroidism but may be more severe with the larger doses given for thyroid cancer. Sodium iodide I 131 may cause suppression of the bone marrow, resulting in anemia, and reductions in white blood cells and platelets. It also may cause acute leukemia.

Other important side effects that can occur with large doses include symptoms of:

Thyroid crisis (due to the release of large amounts of thyroid hormone), severe inflammation of the salivary glands, and chromosomal abnormalities may occur. On day three after treatment, a constellation of signs and symptoms may occur including:

Finally, temporary hair thinning may occur two to three months after treatment.

Medically Reviewed by a Doctor on 7/24/2015

Quick GuidePancreatic Cancer Symptoms, Causes, and Treatment

Pancreatic Cancer Symptoms, Causes, and Treatment
FDA Logo

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

RxList Logo

Need help identifying pills and medications?

Use the pill identifier tool on RxList.

Subscribe to MedicineNet's Cancer Report Newsletter

By clicking Submit, I agree to the MedicineNet's Terms & Conditions & Privacy Policy and understand that I may opt out of MedicineNet's subscriptions at any time.

Health Solutions From Our Sponsors