Alan,
Since you see your neuro pretty soon and are about to start another treatment (steroid or else), you may find some info at this link
http://neuromuscular.wustl.edu/mtime/mgrx.html
about the different possibilities, pros and cons and also some ideas about the time required for a medication to start to act.
For exemple, in my case, it took Prednisone 5 months to get rid of most of my symptoms and I was under Mestinon+Prednisone+Cellcept right from the start. Fortunately the improvements begun after only about 5 to 6 weeks.
IVIG and plasma exchanges were of no use to me.
Also remember that not two MG'ers seem alike… and that MG often means patience…
Maurice.