My neuro had me start with 30 mg once a day (usually in late afternoon) for 3 days.
If I was able to tolerate that, go to 60 mg once a day for 3 days.
Then 90 mg. for 3 days, and 120 mg. for 3 days.

If, at any time during that trial, I started feeling bad, I was to go back down to the lower dosage, and see if I was still able to tolerate it.

I think what she was trying to establish was: 1) If I had MG; and 2) What dosage I could tolerate.

I was able to tolerate 90 mg without any problem; 120 mg laid me out on the couch, wanting to puke my guts up. From there, we were able to establish how often I needed to take it (every 3-4 hours, depending on how "active" I am on any given day).

If you aren't able to tolerate it at all, you either don't have MG or you have a case that isn't treatable with Mestinon.

It's important to have some "consistency" when trying to figure out if Mestinon will work for you. If your doctor doesn't know this, it may be time to find a new one....