I just posted this on another thread earlier today...it must be Lithium Week:
"Experts don't understand the exact mechanism, but the drug lithium can prevent your thyroid from functioning properly. Lithium is known to cause goiter (an enlarged thyroid), as well as hypothyroidism, and chronic autoimmune thyroiditis. There is also a link to hyperthyroidism in some patients."
Chronic autoimmune thyroiditis would be Hashi's.
So, would you think that despite only taking it for 6 weeks as a child, it could still have an effect on thyroid function several years later?
I don't know. If it really can "cause...autoimmune thyroiditis", then it is possible. I have never read a scientific study that actually established a causal link between lithium and Hashi's. If you find one, I'd love to see the link. However, I have read of a number of people who became hypo on lithium since it inhibits the thyroid's ability to produce T4.
Antibodies can be present for years, or even decades, before they do enough damage to cause labs to go out of range and to produce symptoms. Hashi's is the most prevalent cause of hypo in the developed world, so you certainly don't have to have taken lithium to get it.
Be sure your doctor orders both TPOab (thyroid peroxidase antibodies) and TGab (thyroglobulin antibodies) since both are required to rule out Hashi's.
Are you currently on thyroid meds? Does your doctor test FREE T3 and FREE T4 as well as TSH?
I've been on 25mcg of levothyroxine for 6 weeks now. I only had a few good days during my second week, but now Im back to feeling the way I was before. I was only told a TSH number over the phone, but when I called back to schedule my 6 week blood test, I asked about FT3 and FT4 and the nurse told me what all was included in the thyroid panel, by sending me here:
Looks like FT4 is looked at, but I don't know about FT3. I asked about the two antibody tests, and if they could be done this week too. She said sure, but I'll ask again to make sure it's included. She also said that she would give me a copy of the results when I came in. So if that info is on it from June, I'll post it.
It's not unusual to not feel any better or even feel a little worse when starting meds. The initial dose is usually lower than the dose we end up on. Also, your body's been compensating for the lack of thyroid hormones for a while, so everything has to rebalance. However, it's usually best to start out low and increase as tolerated to avoid hyper-like symptoms from too much, too fast.
I followed your link and found this:
"Test Includes: Free thyroxine index; T3 uptake (THBR); thyroid-stimulating hormone (TSH); thyroxine (T4)"
This is not what you want at all. FTI (free thyroxine index), T3 uptake and thyroxine (which is total T4, not FREE T4) are all considered obsolete tests of little value.
These are what you want:
The first is FT3, and the second is TSH and FT4. I can’t believe (yes, I can) that Labcorp doesn’t have a thyroid panel that includes FT3. As I said, that's total T4 in that panel...not the same at all. T3 uptake is actually an indirect measure of T4. You want to get the nurse to change what she's ordering.
Thank you so much for the links. Since she sent me to the site, I just assumed all that technical garble was free T3 and free T4. Im gonna ask for the following:
224576 - TSH, Free T4
010389 - Free T3
006676 - thyroid peroxidase antibodies
006692 - thyroglobulin antibodies
I don't like telling people how to do their job, so hopefully I'll have enough of a spine left Friday to do so. I am grateful that this doctor finally figured out what was wrong since the others didnt, but when I look back at it, he was just the lucky one that got an out of range TSH. Wished I had known more about thyroid conditions. I had excuses/theories for every symptom.