Hi there, I can't say what is causing this problem but I can say that I too have a bit of this problem and I don't take any medication because I react badly to it all. Maybe it is a part of the MG after all, I have learned a lot from this site since I was Dx'ed 18 years ago, many things that are MG related they told me years ago wasn't so keep telling us things that are happening and maybe some of us won't feel so "dumb" about what we are feeling.