Asthenopic (eye strain) symptoms in the eye are responsible for much of the severity in CVS. Proper rest to the eye and its muscles is recommended to relieve the associated
eye strain. Observations from persons experiencing chronic eye strain have shown that most people who claim to be getting enough sleep are actually not. This, unaware to them, causes the eye strain to build up over a period of time, when if they had obtained seven to eight hours of uninterrupted sleep, their eye muscles would have recovered during the sleep and the strain would not have built up. Computer workers are often advised to take breaks and look at distant objects. A routinely recommended approach is to consciously blink the eyes every now and then to help replenish the tear film and to look out the window to a distant object or to the sky—doing so provides rest to the
ciliary muscles. An example of a common catchphrase is the "20–20–20 rule": every 20 minutes, focus the eyes on an object 20 feet (approximately 6 meters) away for 20 seconds. This gives a convenient distance and timeframe for a person to follow advice from an
optometrist or
ophthalmologist. A number of computer and smartphone applications adjust the computer video color temperature, reducing the
effects of blue light emitted by the screen, particularly at night. Dry eye is a symptom that is targeted in the therapy of CVS. The use of over-the-counter artificial-tear solutions can reduce the effects of dry eye in CVS. Prior to using artificial tear solutions, it is necessary to check if dry eye is the actual cause of the problem (measured by a tear meniscus test) or whether there are no actual symptoms of dry eye at all. Dry eyes because of CVS can also be treated using moisture chamber glasses or humidifier machines. Office spaces with artificially dry air can worsen CVS syndromes, in which case, a desktop or a room humidifier can help the eyes keep a healthy moisture level. At night, CVS can become worse. It is recommended to use a dark user interface while working at night on the computer. Several browser and OS settings or add-ons exist to darken the user interface. A 2017 randomized controlled trial evaluated macular
carotenoid supplements (
lutein,
zeaxanthin, and
mesozeaxanthin) in people with high screen time usage. The supplement group had statistically significant reduction in self-reported headache, eye strain, eye fatigue and sleep complaints, but no reduction in neck strain or blurry vision. A 2021 review investigated suggested therapies for CVS and found little supporting evidence for the following: switching to bi- or multi-focal glasses to reduce eye strain, or using glasses that block
blue light. The same review reported "low-certainty" in
omega-3 supplements as a method to combat CVS.
Eyeglasses Decreased focusing capability is mitigated by wearing a small plus-powered (+1.00 to +1.50) over-the-counter pair of
eyeglasses. Wearing these eyeglasses helps such patients regain their ability to focus on near objects. People who are engaged in other occupations—such as tailors engaged in
embroidery—can experience similar symptoms and can be helped by these glasses. A
Pacific University research study of 36 participants found significant differences in irritation or burning of the eyes, tearing, or
watery eyes,
dry eyes, and tired eyes, that were each improved by amber colored lenses versus
placebo lenses, but in a follow-up study in 2008, the same team was not able to reproduce the results of the first study. A study sponsored by the lens industry has shown blue light-filtering lenses decrease specific aspects of light emissions. Theoretical reductions in
phototoxicity were 10.6% to 23.6%. Additionally,
melatonin suppression was reduced by 5.8% to 15.0% and
scotopic sensitivity by 2.4% to 9.6%. Over 70% of the participants in this testing were unable to detect these changes. The expansion of technology has led to more individuals utilizing computers and televisions which increase the overall exposure to blue light. Double-blind trials however, have shown no evidence to support the use of blue light filtering lenses for digital eye strain caused by blue light from electronic screens. ==Prevalence==