I take Mestinon to treat my POTS/Dysautonomia as well as for my MG, and it helps me immensely. In fact I take it more for that than for the MG, as it isn't very helpful with the MG but very helpful with the near syncope, chest pain, shortness of breath, and heat intolerance I experience from dysautonomia. Before Mestinon, I was almost incapacitated from it. I could not walk up the stairs or up a hill without having to collapse to the floor, and would black out after any bath or shower. Forget standing in place, everything would start to swim...and in heated places, wearing a mask, etc...much worse.