Lithium and thyroid dysfunction

I am sort of confused.

- my thyroid was functioning normally before Lithium
- eventually, on Lithium, I developed underactive thyroid
- I was put on synthetic thyroid hormone and was OK for a while
- then I became very sick and was taken to urgent care by a coworker. "Nothing nothing nothing wrong with you!" - sent home with no answer
- then they called me back late at night as they got the last test result in and knew the answer - severely under active thyroid
- my synthetic thyroid hormone dose was increased. I worked from home for a week or two before extra synthetic hormone kicked in because I literally had no physical strength to move my body. Sat at the computer though.
- in Feb of this year I went off Lithium and off the synthetic thyroid hormone, assuming that I did not need it while OFF Lithium
- I do not eat much (small appetite) but keep putting on weight, so Confused suggested a thyroid check, and, SURPRISE,
- I still have under active thyroid and need to be back on the synthetic hormone (at first, a low dose for two months and then re-check and follow-up).

Free T4 is normal.
TSH is High (==> low level of the thyroid hormone)
TSH 5.37 Normal range=(0.34 - 4.82) uIU/mL H

The endocrinologist does not know if Lithium can cause damage that lasts beyond the time Lithium is taken.

Has anybody had that experience?

My understanding is once your Thyroid is messed with by Lithium or other medications you will most likely always need medications to suppliment your thyroid and keep things in a good balance.

Yes it Sucks, But Thyroid problems can happen to damn near anyone.

I have an underactive thyroid, but I have never taken lithium. It is a hereditary problem for me. Maybe it is just coincidence that both coincided. I remember before my mom was diagnosed she had to be admitted to the hospital because her depression got so bad. It turned out that her underactive thyroid was the culprit.
Bluemountains

You are right. Getting TD from AP's would have been way worse. At least there is a synthetic thyroid hormone to fix me.

i am female, 66, bp2, and have been on lithium for more than 35 years. i have had some great drs. in the past who have told me that lithium definitely affects the thyroid (have been on thyroid meds for as long as i can remember) and also lithium has affected my parathyroids...had to have most of them removed w/just a small portion of the parathyroid remaining. have tried other mood stabilizers but for me, in spite of the health issues associated w/lithium, i will be on it til the day i die.

I am sorry to hear this. I am not sure you can be on it till the day you die, as I wish you a happy long life. My understanding was that Lithium is not used after age 70 due to kidney issues people develop on Lithium in their old age. Please research it - I last checked in 2009 and my knowledge may not be up to date.