Hi, I Had My Thyroid Removed A Year Ago. Since

Hi, I had my thyroid removed a year ago. Since then I've been on Levathyroxine and the dosage has been changed several times. For the last 4 months I've been on 88 mcg and have had a continual problem..daily... of rashes and severe hives. Have been to ER twice and med ctr twice as well as dermatologist. Only thing that keeps it down somewhat is prednisone. I really believe that it is due to the med, but my doctor says no.
I disagree... help!!