I have been on Synthroid for 10 years. The first 9 years I was on 75 mcg with no problems. Last year, anxiety got the best of me and it turned out I was getting too much and my dosage was lowered to 50 mcg. Now, I am feeling the anxiety/palpitations starting again. My tsh a month ago was already down to 0.77, so I know it is dropping again. Is this change from being hypo to hyper normal? Thanks for your help. I'm going to go and try to relax.