Wearing lenses for prolonged time, even overnight, with poor sanitation and cleaning habits, and dry-eye syndrome, can lead to an eye infection and corneal ulcer.
Corneal ulcer (an erosion or open sore on the surface of the cornea) can result in a severe loss of vision and even blindness.

Kindly tell me that for how long can we wear lens continuously. And what are the precautions that we should take for wearing lenses?