Since it hasn't been mentioned yet, I must add this: when we work and focus, especially when using digital screens, we tend to blink a lot less frequently. If tear composition is not good or there are other exacerbating factors (e.g. an AC with high flow), the break-up of the tear film can easily lead to eyestrain and even blurry vision.
In such situations, preservative-free artificial tear drops 3-5x a day can lead to pretty good results. In some cases, one needs to try a few, each for a week or two, before finding the correct one.
Pro tip: any eye drop can cause discomfort for a few seconds, especially if the dry eye symptoms have persisted for a long time.
Further reading: https://eyewiki.org/Dry_Eye_Syndrome
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