What is an I-131 Thyroid Therapy?

An I-131 thyroid treatment is for persistent or recurrent thyroid cancer or for the treatment of hyperthyroidism.

How should I prepare for an I-131 Thyroid Therapy?

Your doctor should instruct you to hold any thyroid medications you may be taking. We also can not perform the treatment if you have had IV iodine contrast in the past four weeks.

How long does the therapy take?

The treatment amount will be determined from a previous nuclear medicine scan you will have done, typically the same day as the treatment. After this test is finished your results will be discussed between our nuclear medicine physician and your endocrinologist to determine your treatment amount. The dose will be ordered by our pharmacy and typically takes two hours to receive. Once we receive your treatment you will be brought back to the nuclear medicine department and our nuclear medicine physician will discuss with you some rules you will have to follow for up to a week and answer any questions you may have. A nuclear medicine technologist will then give you the treatment, which is just a pill to swallow and you will be permitted to leave. Depending on your treatment amount you may be scheduled to return the following week for a follow-up scan. If you are a female under the age of 55 you will be required to have a pregnancy test within 48 hours before the treatment.

It is essential to tell your doctor if you are pregnant or think you might be pregnant before undergoing this treatment because of radiation exposure.

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