Barb
Hives can be caused by a multitude of factors- anywhere from allergies to autoimmune disease. My father was getting hives on a regular basis and went to an allergist. The doctor told him he was allergic to cold and flu bacteria/viruses and put him on very expensive daily injections. About a month later, his company physician, at my dad's annual check-up, was asking if he'd had any medical changes in the previous year. My father explained about the allergies and the medication he was taking. The doctor asked my dad if he'd had his thyroid checked, which he hadn't. The result was that my father did not have any allergies to cold or flu bacteria/viruses, but had a low thyroid. He began taking Synthroid once a day and has been fine for over 40 years now. It sounds like your doctor may be heading in the same direction with the thyroid medication. If you find relief, ask about getting off the other stuff. It may just be covering up your symptoms.