I had severe double vision for the first 5 months after I started getting MG symptoms. My double vision was so bad I couldn't see anything at all besides colors that moved around, because neither eye would work properly...every once in a while I could see out of one eye if I covered the other. The mestinon helped slightly in the beginning, but it wasn't until I lowered the dosage in increments during the 5th month that my double vision went away. I wonder if it was the Mestinon that helped but that it took 5 months to be helpful, or maybe I was on too high of a dose initially. I still get double vision now, but it isn't very bad compared to those first 6 months. I only took Mestinon to help with my symptoms.