Can I sleep in contact lenses?
Most contact lenses should be removed at the end of your wearing time and not worn overnight. There are certain types of contact lens that have been designed to be slept in overnight and worn for continuous periods of a week or more. These lenses should only be left in overnight when specifically prescribed for that purpose, and then monitored by the prescribing practitioner. This type of wear is known as extended wear.
There is another type of gas permeable lens that is designed to be worn overnight, but removed the next morning. These lenses are specially designed to gently mould the cornea during sleep to improve vision without spectacles or contact lenses the following day. Again, these are specially prescribed by a practitioner and the progress monitored. This type of wear is known as orthokeratology, or Ortho-K.