My thyroid has been "sluggish" for ages, but my last bloods showed my TSH at 22.5, then dropping to 9.5 when re-tested. My T4 was a bit below the bottom end of normal. This time for the first time I've had my antibodies tested and I have them, so as I understand it my thyroid will gradually pack up, is that the case? GP has suggested starting on 25mg thyroxine. I am scared as three years ago I saw a private doc who uses bioidentical hormones, she felt my thyroid wasn't great and put me on Amour thyroid, but even though I was on a tiny dose I felt so awful on it that I had to stop taking it. (I felt weak and as though my heart was about to give out, panicky and sleepless, so I am guessing rather hyperthyroid but the dose was so low I don't understand why). So I am frightened of taking the thyroxine, any advice really appreciated.