hi, i had an overactive thyroid problem for years. First, treated with carbimazole, but constant relapses. Finally, in November 2010 i had the radioactive iodine treatment. At that time my T3 was around 16. Since then i saw the doctor twice, T3 was first 11, then 9.6. But last week i started feeling rapid heartbeat and the loss of weight. On monday my T3 was 20. Does this mean my treatment didn't work, or is it a temporary relapse and things will improve again? Thank you