Very low TSH on Levothyroxine.

[Guppy70]

So I've now been on 88 mcg of Levothyroxine for almost 8 weeks. I went through a rough time of subacute thyroiditis starting this spring and was first very hyper then very hypo.

My blood draw just before starting the Levo was:
TSH: 18.70 (0.47-4.68)
Free T4:0.39 (0.78-2.19)
Total T3: 0.94 (0.97-1.69)

I just checked my levels again, first time after starting Levo:
TSH: 0.10
Free T4: 1.31
Total T3: 1.40

I know testing the Total T3 isn't ideal, but my endo don't want to test the Free and unbound T3.
I'm going in next week to see her again and to go over these results. I do feel way better than when I was too low. My under eye bags have gotten smaller and I do have more energy. But now I'm worried she will think my TSH is too low and lower my Levo dose. But that will also lower my thyroid hormones and I'm scared half to death about feeling aweful again.

I've read that a too low TSH can cause bone loss. And a too high TSH can cause thyroid cell growth, one of the reasons they keep it low on purpose in thyroid cancer patients.

But what to do in a case like mine? I don't want my T4 and T3 to get any lower. In fact, I think the T3 could go higher but it's hard to tell for sure without the FT3. I can't say that I do feel "optimal" yet but that might also be because I'm still recovering from this illness?

Will a constant too low TSH make the pituitary gland "shrivel up" and maybe cause other diseases like Cushings? I definitely don't want that. But I also don't want to compromise and have to live with too little thyroid hormones.

I do know that at one point I will be taken off the Levo completely to see how my own thyroid function will do, there's still a chance it will repair itself after the thyroiditis. The thing is though, I've had all the hypo symptoms before the inflammation for about a year before it started.

I've tested my TPOab (within the range) but no other antibodies and I don't think my endo plan to do so either in the future. Autoimmune disease runs in my family, my sister for example have Graves disease.

Thank you for reading!

[Guppy70]

Red Star, gosh, that's fast, just one day! Thank you for telling me, this way I know it's not just in my head.
And gives me some hope that it's just temporary.

[Red_Star]

Thyroid hormone is a narrow therapeutic index drug which means if your dosage changes even a little bit it can cause symptoms.

I went from overt hyperthyroidism to overt hypothyroidism in about a day  after I stopped medication. My cells have "issues".  It was like I had gone right back to the beginning again prior to starting medication! It took two weeks to be able to breath better.

[Guppy70]

Thank you for your answer!

Yes, I'm starting to wonder how this will end if I'm already having symptoms of hypo.
I'm going to wait for 2 weeks and if things are just gonna get worse and worse I think I will call the endo and tell her I want to up the Levo again . At least up to 75 mcg or something.

I don't think I can handle becoming too low again.

[Barb135]

T4 does have a long half life, but your levels were somewhat low to start with, and a drop from 50 to 88 is a pretty drastic change, so you could start feeling symptoms pretty quickly.  

I think you need to get back on the higher dose of med, pretty quickly. This doctor isn't doing you any favors.

[Guppy70]

Is there anyone who knows how fast one can feel symptoms from lowering levothyroxine?
Tuesday morning I started with my new dose, 50 mcg, going from 88 mcg.
Yesterday I felt tired, I even napped on the couch for 1 1/2 hour. Same today, I feel so tired and sleepy, I haven't gotten off the couch at all today.

Can it really be the lowering of meds making me this tired? So soon? I thought that t4 has a half-life of about one week? And can it then just be an adjustment for the body to this shift, and that I can still do well on the lower dose after it got used to 50 mcg?

One good thing is that last night I slept through the whole night when I otherwise wake up several times, often not being able to fall back asleep again. It was a very deep sleep for 8 hours, but I didn't wake up refreshed.

[Guppy70]

Yes, that's why I knew that I couldn't know for sure if it was menopause or not. I had a growth on the one ovary that was suspicious for cancer and I was told I needed the surgery. If it was cancer they would have removed everything and then some and would have had to start hormone replacement right away.
I told my surgeon right from the start I wanted to keep one ovary if it wasn't cancer just because I didn't want to end up in immediate menopause, if I wouldn't have insisted he would had removed both anyways, regardless. Typical man philosophy, lol. We do need every little drop of natural estrogen we can get.

I did go to my GP about 18+ months ago as I was starting to go down hill and told him all my symptoms and that I think my hormones are messed up and if we could check them. He told me I should go back to the doctor that performed my hysterectomy but when I called him I was told he only do gyno surgery and don't handle hormones. At that point I gave up, which was pretty stupid in hindsight. It could have saved me a lot of heartache if I just got a checkup then. Why my GP didn't want to do that beats me.

It could very well be menopause but then it would be so weird that my hot flashes just stopped as sudden as they came on. It's like night and day and they usually lasts for years and years. My moms lasted for over 10 years. But it sounds like menopause and thyroid symptoms are so similar it's impossible to know without labs.
I'm acctually almost scared of this FSH testing, I would feel old if it comes back as full blown menopause, lol. But, on the other hand I can get help.