I had block and replace therapy a couple of years ago for an overactive thyroid. It was successful and I stablished for a year and a half. My recent bloods reveal that my thryoid is fluctuating, sometimes just over sometimes a fair bit over. My GP seems to think I will go underactive at some point and that we should just watch and wait, treating the underactive throid when it finally burns out. Is this good practise? My hair is coming out in small handfulls and I have a very slight tremour in my hands but other than that there are no other symptoms.