One of the cats in Cat's Haven (
at my parent's place) used to have eye problems often so what we'd do is wash them with chamomille tea.
I recently saw chamomille listed as toxic so although I never had any problem with it during the many times I used it nor any side effects of it (and I've used it in different cats) I guess I must mention it.
You could research what would do a good eye wash for your kitty cat. It really helps to control those mild irritations and keeps the eyes clean. I only did it when it was needed though and with time the frequency of the irritations went down a lot.