Hey Nancylee, welcome to the mg site.
Ive had MG for nearly 5 years, and been on mestinon for 5 years. I have a twitch that affects my neck shoulder head area, my head flicks over to the right and my shoulder rises, I assume its from the mestinon, have never told the dr as its very intermintent and doesnt bother me, it must be awful to affect you badly enought to have to go off the mestinon altogether.
It does however affect my stomach etc, and have to rush off to the toilet sometimes, but I do make sure I take it with food, or it really plays havoc. Hope this helps