Night Contacts

While it's typically not advised to wear normal, soft contact lenses to sleep, night contacts are specially designed to be worn while sleeping to temporarily fix near-sightedness. They are specially prescribed by a doctor to correct the shape of your cornea (basically a soft part of your eye in front of your natural lens). To understand how this works, note that when people are nearsighted, it is due to their eyes not being able to focus light all the way to the back of their eyeball where the visual receptors are. The receptors carry the signal to the brain so that we can see. Normal lens (both contacts and glasses), refract and bend the light so that it does go to the back of the retina. Night contacts are slightly different in that they basically adjust our natural lens for us so light will naturally bend to the proper place. The adjustment lasts about 18 hours or so and takes about 4 hours to get your eyes to readjust. It's a great temporary adjustment for people who don't want to worry about that during the day. Unfortunately, if you do forget to wear it at night, you won't be able to wear it during the day (it really irritates your eyes) and will have to resort to using glasses or traditional contacts.

I've worn Nightlens (a brand of such contacts) for about 5 years now without any eye infections or irritations when used at night so I, personally, believe it is a safe product. It has also helped make sure my prescription doesn't get worse over time. Unfortunately, it is pretty expensive (about $500 USD per lens so $1000 USD for both my eyes).

Of course, I'm not a medical professional so please research and do your own research. And with that, have a great day.