I really know nothing about this autoimmune disease but decided to do some searching .... Here is what Dr. Weil says and what he recommends. I'd bet most who deal with this have searched on the alternative therapies. Potassium seems to come up a lot in a lot of the links I've read. Prednisone comes up a lot but I know how damaging that drug is.

Myasthenia Gravis | Dr. Weil's Condition Care Guide

my mother in law just died from MG. it was terrible for her. they intebated her and she had the plasma phoresis done and got her off the ventilator but by then she became a no code. she did not want to be to be put on life support again. so they moved her a nicer room and said good bye as jeff flew back home, was not given any information. had he know she would have another anti bodies act he would have not left. 8pm her vitals were normal. but by mid night they were not and they tried getting a hold of the family. only time my brother in law phone had been turned off. she died peacefully with 2 nurses the and the team doctor there providing comfort measures only.... at 1am she died from mg antibodies attacking her frail body and her poor heart could not take it any more.
It has been a very hard mothers day for them both.
I should call my brother in law and let him speak of her. There have been a lot of nice words said about her on face book. She was a lovely lady smart in every way. always giving to charities, they would send her flags, mocasons from the indians, dream catchers some times then they would send her a dollar, she liked those charities. and would send them a donation.
She freely used to help get little flags for the neighbors to enjoy, one person would put them in the ground in front of the house. they did that for years. She gave us money to help buy our house.She was very generous to ward other people and was sacrifycing her self. used safety pins to hold her pants up. she had lost so much weight, she basically bought her own funeral clothes every thing was right there. I think she knew that she was dieing and made every thing as easy as possible for the boys to take care of her finances.
She will be missed by many.
loved her.
bizi