I have Hurthle Cell Carcinoma, minimally invasive, diagnosed in 2000. My TSH has remained pretty low since RAI. However on a visit to my Internist he checked my TSH among other things and it was 72.8. He wanted to increase my sythroid from .150 to .250 but I said no way. The last time he changed my dosage I got thyro-toxic. My endo said (via nurse)just take the .150 first thing in the morning with no other medications and have it rechecked in 3 weeks. I have been taking my synthoid the same as I have for years. Any idea's to the sudden spike in my TSH. (no other thyroid tests were run so I don't know what my T3 or T4 is)