With the technological advances we have today and the continued use of the computer (either for personal use or for work), we are increasingly exposed to a condition called asthenopia or eyestrain. Moreover, if the cause of eyestrain is the use of computers, you might have trouble focusing on the screen and you may visualize colored stripes or flashing images after you finish working.
Recommendations 
Medications are not necessary to treat this condition. All you need to do is change your habits, both at work and during leisure time, and adjust the way you read or work on the computer. Follow these recommendations to reduce fatigue:
- Work in an illuminated area, with the light directed toward your workplace. If necessary, use a bright light source.
- If you're reading, try to place the light source behind you and direct it toward the document. Try not to have a source of light pointing directly into your eyes.
- If you're working on your computer, make sure the monitor is placed 51 to 71 inches away from your eyes. This can also be the distance of the arm. If you need to be at a closer distance to read, increase the font size of what you're reading or zoom the screen. Make sure the top of the screen is at the level of your eyes.
- Consider revising the brightness of the screen. An excess in the brightness and luminosity make it very difficult to see objects on the monitor, causing tired eyes. To check brightness, sit in front of the computer while the monitor is off, so you can see the images and reflected lights.
- Adjust the monitor so that sources of light are placed aside, at a right angle toward the monitor. It's best to use an adjustable desk lamp. Close the blinds and avoid placing the monitor in front of a window or a white wall. If necessary, use a screen protector to minimize shine. You can also adjust contrast and brightness of the screen to a comfortable level.
- Keep the screen of the computer clean. Dust reduces contrast, and therefore increases brightness and reflection.
- To reduce fatigue when working on the computer, place the keyboard directly in front of the monitorso that your eyes are focused on the same direction.
- If you work with reference materials, place them on a document holder next to the monitor,at the same level, angle, and distance as the monitor is from your eyes.
Preventive Measures
Besides the previous recommendations, it's wise to practice preventive measures in order to keep your eyes protected and in good condition for a longer time. Follow these recommendations:
- Take small breaks. During the day, let your eyes rest by focusing on something different from the computer screen. Take a five-minute break every hour. Try to do something else during this time, like making phone calls.
- Try to stop and move at least once every hour.If possible, lay down and close your eyes for a moment.
- Keep in mind that blinking refreshes your eyes. Dry eyes are usually a result of insufficient blinking of the eyes while working at a computer. Blinking produces tears that help lubricate the eyes.
- If your eyes remain dry even after blinking, consider the use of artificial tears (eye drops).Ask your doctor which drops are appropriate for you. If necessary, wear anti-reflective glasses to work on the computer.
Source:
Eyestrain (2008) Mayo Clinic. Retrieved on December, 2008 from: http://www.mayoclinic.com/print/eyestrain/DS01084/METHOD=print&DSECTION=all
