Poetist, how much Mestinon are you taking if you are taking an additional dose of 30mg 3 or more hours after your scheduled dose? Mestinon generally loses its effectiveness in 3 to 6 hours, so seems to me that your "additional" dose of 30mg should be your next regular dose. (Forgive me if I've interpreted your comment incorrectly and the 30mg is not an additional dose.)

To clarify my initial comment, absolutely discuss any changes with your doctor, and simply "doubling" your dose is dangerous. To the extent you are asking if it's ok to take 120mg at a time, eh - if you need it, maybe yes. But you should be very careful getting to that dose - I was in the hospital when I ended up on that, and we got there by starting at lower dosing schedules (which were insufficient for me and I kept crashing) and working up to 120mg every 4 hours. It is a fairly high dose of Mestinon - generally from everything I've read and heard the recommendation is to not exceed 360mg spread over a 24 hour period. But it works - for me, and I got to that dose with my neurologist's approval and guidance. You and your doctor have to figure out what works for you.