I had thyroid lobectomy 2008. Lab sample showed papillary cancer. The aim after operation was to suppress TSH to be undetectable and prevent a cancer on the remaining thyroid.Over 5 years on increasing levothyroxine TSH is now 0.77 but my T4 is way out of range at 46. T3 is 8. I am on 300mg levothyroxine and feel ok. I now have been told To accept failure to totally suppress TSH but concerned about long term effects of 300mg levothyroxine.