Nov, so sorry for all you have been through. I had large nodules on my thyroid when I was 21 (34 years ago) and had half of it removed. They did not do antibody test then but it is assumed by my endocrinologist it was Hashimotos. I a on synthroid - 87 a day, I still have half a thyroid. I think I had MG for over 15 years, but was officially diagnosed 2 years ago. A lot of MGer, I think I read 1/3, have thyroid issues prior to MG. Which antibody level was positive - Achr? There is more than 1. Most MGers are ACHR positive and many have hyperplasia of the thymus, another endochrine gland. You should ask your neurologist for a scan of your thymus. Many MGers have their thymus removed and experience remission or improvement of symptoms. I highly encourage you to see a neuromuscular specialist at a large teaching hospitals that see MG all the time. MG is so rare most local neuros have never seen it. Mestinon only temporarily improves symptoms for a few hours. Most MGers also take a disease modify drug like an immunosuppressant. Most start on prednisone because it is fast acting but also take cellcept or imuran which take months to start working. Prednisone has lots of side effect, they start to wean you off as the long term drug like cellcept kick in because it has fewer side effect.

Good luck on you MG journey and keep us posted on how you do,
kathie