If your eyes feel tired, sore or gritty, you may have 'dry eyes', or 'blepharitis' , or both.
Dry eyes is a common problem as people get older, and in diabetes.
The eyes may feel scratchy or gritty, as though there is something in them. They also be a little itchy, and they may be red. Blepharitis is described on a different page of this web site in more detail. It causes sore eyes by stopping tears spreading evenly. Dry eyes' occur when there are not enough tears to keep your eyes lubricated, or the tears that are produced do not spread evenly across the eyes.