I agree that it is your choice regarding the thyroid. I will say that going off Lithium doesn't always fix the thyroid. I've been off Lithium for maybe 4 or 5 years now and must still take the large dose of 150 mcg Synthroid. I don't see that ever changing, in my case. Like others wrote, I don't see that as a big deal. I have zero side effects from Synthroid and it's a rather small pill.

I went off of Lithium because of kidney damage. That is a very big deal. If I stayed on Lithium and my kidney damage worsened, obviously there wouldn't be any small pill to easily address that.

I don't mean to scare you about kidney damage. Of course not everyone gets that from Lithium.