My bad side effects with the mestinon are gastrointestinal. It speeds up my whole digestive tract. I'll spare you the details..........
As I have continued taking it, the problems have decreased. If I space the dosages too close together, I will get muscle spasms, especially in my tongue. Who ever heard of a tongue spasm? Crazy stuff.

If your daughter is using the mestinon as a trial, I would keep careful notes on what it does. If it does not work, then that is a significant thing for the trial.