I have the same situation. I think my Cellcept has kicked in but during the reduction of Prednisone I started getting weaker. When I went below 20mg I started getting weaker. I'm at 15 now but starting a session of 16 IVIG treatments. I feel the same as you about the Mestinon, it does nothing. I stopped the 180 time release at night on my own and can't tell any difference. I had my first IVIG dose on tuesday and I feel a little better. That's a first for me. I usually don't get a bump. I have 4 positive antibodies. We did try Imuran for 12 months and it made me sick as a dog. I lost 35 pounds.
Mike