I was diagnosed with Graves disease 11 years ago. My endo prescribed Methimazole, which I was allergic to, so he told me he didn't want to prescribe me anything else because sometimes the allergy kills the thyroid. It apparently did, because all of a sudden I was hypo and I had to go on synthroid. Since then, I lost my health insurance and got handled by my PCP instead of the endo (cheaper).