The same thing happened to me last November after being off Prednisone for a month. Neuro started me back on Pred beginning with 5mg and kept increasing it, but no help. Mine was so bad I couldn't drive, put on make up, and had trouble walking about in unfamiliar territory. After 3 weeks still no improvement in DV, and then started to experience general MG symptoms which up to that time I did not have. Long story short, he put me in the hospital, had 4 plasma exchanges, and moved up my thymectomy. About a week after the surgery the DV finally went away and has been gone since then. I'm now off the Pred again after 5 months on it, and am keeping my fingers crossed it doesn't come back again.

For me the only thing that works for DV is Prednisone. Mestinon doesn't help if I already have the DV. I've always been on Mestinon since diagnosis in July 09.

Sorry your DV is back. I know how bad it can get. Hope you and your neuro find a quick solution.