I am the same way. I am pretty much done around 4 or 5pm. I have much more energy when I wake up, and get worse as the day progresses, even with mestinon. I have other autoimmune disorders too, though. I really think my fatigue is due to muscle weakness/muscle fatigue also. I think if they're saying your fatigue is not from mg, then they should be checking for other causes. Idk why they don't believe it's from mg. I have this conversation with my neuromuscular dr and I don't get a satisfactory answer. My husband can tell when I am tired because my voice gets weak and posture becomes slouchy. this seems like muscle fatigue to me ?