Generally working at computer that long leads to dry eyes. Also reading, computer, TV and movies lead to dramatic decrease in blink rate which aggravates the situation. Try several brands of artificial tears such as Genteal, systane, Blink, Hyoptears or Retaine. Use every 3 hrs. Make sure you don't have air blowing on you at the computer. Every 10 minutes look away from the screen, look at the farthest thing you can see such as out the window or down the hall. Blink forceful 5-6 times. This will usually take care of the problem If still symptomatic read the extended section on my home page about treatment of dry eyes and see an Eye MD ophthalmologist for an exam.