It's quite funny, but Ephedrine (which has a somewhat similar mode of action) was the first effective treatment described in MG.
It was found by a physician who suffered from myasthenia in the 1930s (a few years before Marry Walker discovered treatment with AchE inhibitors).

http://jama.jamanetwork.com/article....110#qundefined

Ventolin was first used, to the best of my knowledge by a neurologist in Mayo clinic for the treatment of certain types of congenital MG. He is now conducting a clinical trial.

http://clinicaltrials.gov/show/NCT01203592

I decided to try taking it, based on the way I understood the mechanism of my illness. (none of the neurologists involved in my care ever suggested it). At that time I was nearly bed ridden, unable to sustain any activity for more than an hour and required frequent respiratory support. It led to significant improvement. For the first time since my 1 year old niece was born, I was able to hold her for a few minutes on my lap without having severe breathing difficulties.

At a later stage my current neurologist added mytelase (as mestinon and neostgimine were no longer effective). I started taking, by his advise, some nutritional supplements, because my nutritional intake was very poor for more than a year due to my chewing and swallowing problems. This led to some improvement which made me think I should gain a better understanding of nutrition and other environmental factors that can effect my illness.

There is still a lot I have to learn, but with more knowledge and understanding I have much better control over my illness. (although, I am no where near remission or even near leading what normal healthy people would consider a normal life).