This week, Douglas Black, an optometrist at Darling Eye Center in Bluffton and on Hilton Head Island, discusses the dangers of keeping your contacts in overnight.
Question. Sometimes -- OK maybe more than a few times -- I forget to take my contacts out at night. It doesn't seem to bother my eyes day to day, but are there long-term problems associated with keeping your contacts in for too long or sleeping with them in? Are the only ones that are safe to sleep in the extended wear "day and night" lenses? Am I doing a good enough job cleaning them if I just take them out and let them sit in a little cleaning solution?
Answer. It is really never a good idea to sleep in any contact lens. The cornea, the front covering of the eye, is the window that we are constantly looking through. For the cornea to be clear and healthy, it must receive a good supply of oxygen. All contact lenses sit on the cornea and act as a barrier to oxygen. During the day, this is not a big issue because as we move our eyes around and blink, the lenses move slightly, allowing tears and oxygen to transfer underneath the lenses, reaching the cornea. However, at night this movement does not occur. Contact lenses become dry and fit very tightly onto the cornea. On top of that, since the eyes are closed while sleeping, there is not much oxygen reaching the cornea to begin with.
Studies have shown that people who sleep in their contact lenses are 15 to 25 percent more likely to develop serious eye infections than are those who remove their contacts nightly. And when these problems develop, they tend to be more severe in people who sleep in their contact lenses, since the eye's natural defenses are weakened as a result of this lack of oxygen supply. Also, a closed eye with a contact lens on it is a "perfect storm" situation for bacteria and/or viruses to grow.
Contact lenses that are labeled as "extended wear" have gone through the FDA process to be approved to be marketed as such. These lenses are made out of materials that allow more oxygen to transfer through the lens to the cornea than do other lenses. This is an advantage when comparing these lenses to non-extended wear lenses, but the amount of oxygen being transferred to the eye pales in comparison to having no contact lens on the eye.
Cleaning and disinfecting your contacts are definitely important steps to keeping your eyes healthy. Most people who wear disposable contacts use "multipurpose" solutions. Peroxide-based solutions are the best at disinfecting contact lenses. Although many solutions market themselves as "no rub," it is still a good idea to rub your lenses to remove more debris from them.
When you look at the potential dangers involved with sleeping in contact lenses, it really makes sense to remove your contacts each night. It takes the typical contact lens wearer an average of 45 seconds to remove their lenses and put them in a case with disinfecting solution. That means that taking less than one minute out of your evening can help to greatly increase your chances at maintaining healthy eyes.
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