I've often wondered if I truly had PD because I never felt 'off' periods. I assumed they'd be periods of stiffness or slowness or maybe dizziness. None of which I seem to have. But I just watched U-Tube videos about PD I saw that double vision caused by lack of convergence is a sign of PD. I have convergence problems. I've had it nearly 5 years.
Convergence problems is when the eyes no longer work together. Each eye focusses on something but the two eyes don't focus on one thing. When racing my eyes would stop working together. One eye would focus on the path directly ahead but the other would be focussing on a bush or tree somewhere off to the left of the path.
I got into a habit of carrying bandaids so I could tape one eye shut til finishing the race.
Most days the convergence problem happens late in the day. Today I took Rytary at 8, 3 and 10 and I've had no convergence problem at all day. It seems to easy, remembering to take the pills on time prevents the double -vision problem.