Hi…it's been many years since I was I131 treated for Graves' Disease. Doing some research on behalf of a friend, I'm curious to know what the average mCi dosage is these days. Back when I was treated, average dose was around 10 to 15 mCi. However, I had a rather significant thyrotoxicity and because of the high uptake I received only 5/6 mCi. I believe the radiologist factored in my body size and my young age as well. That 5 to 6 mCi knocked me into permanent hypothyroidism within a couple of months. That's been a few decades ago.

TIA for your help…

I don't happen to know what an average dose might be. I think, though, that today's dose is typically larger than the one you received. They still factor in the results from the uptake and scan tests (size of thyroid, degree of activity), but most of the time nowadays our doctors seem to have the intent to “ablate,” (destroy), whereas many years ago, they were often content to try for “euthroid” (normal levels of thyroid), and accept hypo if it came, or do a second dose of RAI if the first dose wasn't sufficient.

Thank you. Could you give me some idea, however, of what the members of this forum report…what seems to be a typical range for the members here?

As I said, some years ago the typical range was approximately 10 - 15 mCi. Are your members usually reporting higher dosing than this?

TIA…

Good Morning,

I had 26 mCi on April 23, 2012. It sounded like a lot to me at the time and I questioned the radiologist about it but he insisted that was what I needed. I will have another ultrasound of my thyroid at some point but that has not happened yet. Now the issue, of course, is trying to adjust my Levo to the right dosage which hasn't happened yet. I just drew labs this morning and have another endo appointment on Halloween. Right now my dosage is .15 daily. I feel better but not great. I hope this information helps you in your care plan. It is not an easy one to make.

Best Wishes,
MVK

Hello,

My endocrinologist who is also a professor at the Medical University near where I live in SC, is up on the latest as he told me average dose is 8-15 mCi. I had 15 mCi myself May 2012. I consulted with two other endocrinologists who use up to 29 mCi; for Graves, that is, so it seems that it varies some. I know in years past they used a lot less and found that some patient's thyroid's were not resolving well enough where people needed a second dosage; it was with the thoughts of making the patient Eurothyroid. Seems today with some endocrinologists it is a little different yet I find it varies only from myself seeing four different endocrinologists with all different approaches….beach

In one of the YouTube videos posted by GDATF from a conference a professor at UM Ann Arbor discussed a specific formula that was, i believe, a multiplier (.2, but I am not sure) x size of thyroid divided by percentage uptake. In other words, the lower your uptake the higher your dosage. I had a low uptake of about 30% and a small goiter so my dosage was 21.6mCr. If you had a small goiter and a high uptake you might have a lower dosage. It makes sense if you think about what the uptake is and what you are being given, i.e. iodine. This video is YouTube along with a few others posted by GDAFT.

So the average dosage is really a function of the average goiter and uptake — I think!

I received my dose last Wed., it was 30 mCi. My Dr. said they base it on the size of the thyroid itself.