Refocus every ten minutes by looking out the window or around the office.
Each hour close your eyes and let your face soften.
Slowly roll eyes in a circle.
Take a few breaths, and return to action.
For soothing relief, rub palms together very fast till they get warm, then place them gently over your eyes. Softly hold them there till heat dissipates.
Office Yoga: Simple Stretches for Busy People. Darrin Zeer, pg 41