T3 Uptake

[Jwls222]

I've been treated for Graves Disease with radioactive iodine 10 years ago.  Since then I have been taking Levothroid.  I recently changed to 150 Synthroid.  Recently, my lab results came back as follows:

                     Result     Range
TSH               0.3         .2 -   3.8
T4                  7.4       5.9 - 12.5
T3 uptake      40.5      22.5 - 37
T7                  3.0         1.3 - 4.6
Vitamin D       21.6         30-100

Can you help me understand the T3 results that are out of the range?  Do you think there is a correlation between Graves Disease and my inability to metabolize vitamin D?  These are my results after taking a supplement for 2 months.  What questions should I be asking my doctor, medicine, or other suggestons to ensure that I get my system to be in the proper ranges?

[AR-10]

Just to clarify, that's one pill of vitamin D3, not 3 per day.

[AR-10]

This is what I found to describe the T3 uptake test. This is written by a doctor, and is his opinion.


T3 Uptake: This test is mentioned only as a warning not to use it. In fact, it does not measure T3 levels at all – the name is misleading. It is an old test designed with a purpose of indirectly measuring T4! It was developed before we were able to accurately measure T4 levels. The assumption was that if the patient had a high T4 level, the blood proteins would be saturated with it. Therefore when mixed with T3 (which is easier to measure), the blood proteins would take up very little T3. Thus a low T3 uptake implies elevated T4 levels and vice versa. Thus the T3 Uptake test is actually an antiquated, inaccurate way to measure T4 levels.


I pulled it from this link;

http://www.drrind.com/thyroidscale.asp#scale

It looks like your doctor needs to move into the 21st century. The T4 test run on you is an old style test, as well.
You should be getting a Free T3 and a Free T4 test instead.

Vitamin D deficiency is common with thyroid conditions. Are you taking a supplement? Mine was low, and my doctor has me taking 1,000IU of D3 per day.

[stella5349]

You probably are having some hyper symptoms due to your TSH on the lower side of the chart. I would think if you could raise the TSH back to 1.0 the T3 may lower a bit. Your body is converting the Synthroid from the T4 into T3.

The switch to Symthroid may be the reason. Synthroid is the better of the two to take and your body may be confused on the new meds and haven't quite balanced out. I small med change maybe lowering the dosage of Synthroid may help. Going to a .125 may be good for you. Did your doctor advise on lowering that due to the TSH level?