If you work for long periods of time on a computer, protect your eyes by taking frequent breaks. You might have noticed that your eyes often feel strained, tired and itchy during regular working hours. This is probably a good indication that you're over working them. Get up and stretch for a few minutes, offering your eyes some time away from the screen.
If you regularly wear contacts, keep a pair of backup prescription eye glasses. When experiencing irritation in the eye, you should remove the contact and wear a pair of prescription eye glasses. Keeping a contact lens in your eye while the eye is irritated can turn this seemingly small problem into something much larger, such as corneal ulcer.