Here you go, Brian. Like I said, there's not a lot out there and there needs to be more studies on this. There should be an MG specific study done.

http://www.ncbi.nlm.nih.gov/pubmed/7189263

http://www.ncbi.nlm.nih.gov/pubmed/15106728

http://www.ncbi.nlm.nih.gov/pubmed/15683849

And this one by Dr. James F. Howard refers to the possible longer lasting effects of Mestinon, although it doesn't delineate why.

http://www.ncbi.nlm.nih.gov/pubmed/2540433

I hope that helps. Maybe you can dig around on Pubmed and find more.

Annie