My Boyfriend Was Diagnosed With MG. He Is On Medication

My boyfriend was diagnosed with MG. He is on medication and waiting on the insurance to approve the antibody transfusion. My question is that about how the medicine is working. I don't know what the drug is but he is on a time release capsule that he takes twice a day. In between these doses if he feels the symptoms coming on such as his eyelid drooping, mouth drawing down and the hand/arm feeling like dead weight and his hand almost becomes atrophied, he is allowed to take one or two tablets of the fast acting medicine. This seems to help, but my question is each time these symptoms come about is that having any long term affect? Will there be a time when the medicine will not treat the symptoms? All of these symptoms come on at the end of the day when he needs to be resting but he doesn't take to that advice at all.