Ok sounds about right as for a normal dose. I was able to find an old reference to what I was taking and actually I was on 2 separate anti arrhythmic drugs. You may want to ask about one less common but I found to be (I believe) better with less side affects. The 2 i was on amiodarone 200 MG 1 per day, and mexiletine 200 mg 3 times a day then towards the end a third one Sotalol 120 MG twice a day. But this was when things were really getting bad and it was 3 months later when I was looking at transplant.
Now in the beginning when I was only on the first 2 the amiodarone was at 400 Mg so your doses were actually on the low side at 200 mg. Im not sure when the length of the treatment affected my Thyroid but when I got to Mayo the Cardiologist noticed that my ears tips had a light shade of blue. This she said was from the Amio. I did not notice it as it was very light. it was also then that I was told my thyroid was beyond use and was removed. So your not wrong there is long term effects on that medication. But I look at it this way. It got me 10 more years before I needed a more drastic treatment like transplant. But your smart to consider all area's before making any decisions.

I also might add that when my original problem started my cardiologist tried 2 other medications first before Amiodarone. One was lisinopril but I got hives with that one. I don't remember the other one. So I was kind of at a place where Amiodarone was the last option. Maybe discuss your concerns and see if there are other options available in your case.