I have been using refresh tears eye drop from last 9-10 months.i use it thrice a day according to screen use.sometimes i get crystals on my eye lashes in morning. Is it harmful or habit forming to use the refresh tears for this long time? Can i continue this? What are the alternative or should i continue this? Please guide me what should i do. I am also doing some eye exercises and following 20-20-20 rule.