Hi. Thought I'd just add my story to the thread. I'd had very low level tinnitus for maybe 20 years. I could go weeks without noticing it. Then last year my Dr said my thyroid levels were low and he thought I would benefit from medication so he started me on 25mg thyroxin even though I'd not complained of any symptoms. After 1 month he put my dose up to 50mg and then up to 100mg 1 month after that. About 1 week after starting on 100mg I noticed my tinnitus had got worse and it got progressively worse thereafter. I told the Dr I thought it was the thyroxine causing it and suggested I drop back down to 50mg which I did but by then my tinnitus was horrendous and so I stopped taking it altogether. That was 9 months ago and I still have very bad tinnitus although I feel I have started to habituate. A couple of months ago I had an MRI scan which showed that I have an acoustic neuroma. The consultant said this was a possible cause of my T but he couldn't say for certain. Since then my Dr has been concerned about my thyroid levels again and wants to put me back on thyroxine. So far I've declined as I had associated it with the cause of my T but I'm now thinking that it might just have been coincidence and that the acoustic neuroma is the more likely cause so I think I will go back on to a low dose of thyroxine and see how it goes.