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A 70-year-old female asked:

I had a partial thyroidectomy and the radioactive iodine treatment for the other side due to goiter-nodule with small cancer. synthroid (thyroxine) reduced-why?

1 doctor answer2 doctors weighed in
Dr. Ira Katz
A Verified Doctoranswered
Endocrinology 26 years experience
For RAI to Work: The overall treatment is a little confusing as cancer is usually surgically removed, but there are a few reasons to lower your Synthroid (thyroxine). It may be held for a while so your left over thyroid tries to work and will suck up the RAI. The other reason is when the thyroid cells die they will release thyroid hormone. This could temp make you hyperthyroid. Eventually your dose will be adjusted again.
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Dr. Ira Katz
A Verified Doctor commented
A US doctor answered Learn more
Provided original answer
One other possibility, is that they new about the nodule/cancer and were suppressing it with high doses of Synthroid (since you said reduced dose and not held, I don't know how long ago or by how much) and feel now that it is "gone" the dose can be reduced. To prevent side effects, like irregular/fast heart beats, osteoporosis. This is a little confusing to me without more information.
Jan 31, 2016
Last updated Jan 7, 2018


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