Double vision in Parkinson’s is often caused by problems in moving the eyes and, in particular, by problems of tracking. ‘Tracking’ refers to the eyes moving in alignment from side to side, for example moving across a page when reading. Impaired co-ordination and fatigue of the muscles that move the eyeballs can mean that the eyeballs do not move together in alignment. This can cause double vision.
The problem of double vision is usually improved by anti-Parkinson’s medication. Resting the eyes when double vision occurs is wise and should provide relief.
There can be other causes of double vision that are unrelated to Parkinson’s. If the problem persists, consult an ophthalmologist (doctor who specialises in the care of the eyes).