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You may wear contact lenses to improve your vision because of one of the following refractive errors:
However, these thin, transparent plastic disks pose certain health risks, especially when you wear them overnight.
You shouldn't leave contacts in overnight because oxygen does not reach your eyes efficiently. When this happens, cells in the cornea go into a state of hypoxia (low oxygen). A low-oxygen environment also promotes bacterial growth.
This primary cause and other physiological reasons could increase your likelihood of developing an eye infection. If severe enough, the infection could even lead to permanent vision loss.
When you sleep in any type of contact lenses, your risk of microbial keratitis (a severe corneal infection) increases by 6 to 8 times.
When you sleep in contacts, you don’t let your eyes breathe properly. In other words, oxygen does not fully reach the surface of the eye because of the contact lenses.
When this happens, your eye can grow more blood vessels, and you can experience redness and irritation. You can also have other problems with the cornea.
Contact lens wearers may find that removing contact lenses becomes more difficult because of dryness. In these cases, you are recommended to use contact lens rewetting eye drops before taking out the lenses. Doing this will help prevent damage to the corneal surface.
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Contact lenses have some side effects and risks.
As mentioned before, you can develop redness, irritation, or dryness of the eye. The severity of this problem can vary depending on the type of contact lenses you’re wearing when you go to sleep.
As you’ll read later on, though, some contact lenses are more suitable for overnight wear. Differences in material and design allow for better oxygen flow.
Yet, even then, the risk of eye infection is still present.
Here is a list of symptoms associated with contact lens-related infections:
Some contact lens-related eye infections can cause serious vision loss or even blindness. If you have any of these symptoms, it is important to see your optometrist as soon as possible.
18-20 microbial keratitis infections will occur annually in every 10,000 people who leave in their contact lenses overnight.Centers for Disease Control and Prevention
If you fall asleep with your contact lenses still in, there are a couple of steps you should take immediately afterwards:
Take out your contacts as soon as possible.
Doing this will lessen your risk of infection and further eye dryness. If you find it difficult, then place several drops of contact lens rewetting drops in your eyes and blink. This should help dislodge the lenses for easier removal.
You want to remember to not pull at the contact lenses. This tugging motion could cause abrasions to the surface of your eye.
Hold off on wearing contact lenses for one whole day.
You want to rest your eyes and let them breathe again. Also, be on the lookout for any possible infection symptoms. If you notice something strange, get in contact with your ophthalmologist or optometrist.
Non-prescription contact lenses can result in serious eye problems and even lead to a corneal transplant. If you wear these overnight, the risk increases. It is important to speak with an eye doctor before using this type of lens.
The United States Food and Drug Administration (FDA) has approved different kinds of contact lens for day and overnight wear. These include:
You can use extended wear overnight from one to six nights or up to 30 days.
Because these lenses are made of flexible silicone hydrogel plastics, a higher amount of oxygen can reach the cornea. You’ll see that most extended wear contact lenses are often soft contact lenses.
Only a few rigid gas permeable (RGP) lenses are available and suitable for overnight wear. After each scheduled removal of these contact lenses, eye care professionals recommend that you rest your eyes for at least one day and wear eyeglasses.
Ortho-k contact lenses help change the curvature of the cornea.
In doing so, the eye can focus on objects better. Eye care professionals often prescribe this type of contact lens for people with myopia (nearsightedness).
If you use Ortho-k lenses, you may be recommended to sleep with them on for at least 8 hours per night.
Ortho-k lenses are then removed in the morning, and the wearer can enjoy clearer vision throughout the day with no glasses or contacts.
The risk of microbial keratitis is higher in people who use extended-wear lenses.
If you fall asleep with your contact lenses still in, you should remove your contact lenses immediately and wear eyeglasses for at least a day. If it is too difficult to take out the lenses, place some contact lens rewetting drops in your eyes. This will help provide some extra lubrication and dislodge the lenses without damaging the corneal surface.
If you have extended wear contact lenses, it is possible to sleep with them in for one hour. But each time you sleep with contacts, even if for an hour, you increase your risk of an eye infection. It is recommended to avoid falling asleep with the contact lenses still in.
Sleeping in contact raises your risk of infection because your eye does not receive enough oxygen or remain optimally moist to fight off harmful bacteria and viruses. Also, certain bacteria like Pseudomonas aeruginosa may find it easier to colonize the contact lenses if left in for more extended periods.
Sleeping with contacts may cause headaches, although not always. The headaches may occur because of dry eyes caused by the lack of oxygen flow and moisture. When you have dry eyes, you can become more sensitive to light and squint in response. This constant squinting can sometimes trigger a muscle tension headache.
You should visit your ophthalmology clinic if you suspect you have an eye infection. It is important that you bring your contact lens case with you. Do not throw your contact lenses away. Your eye doctor can culture the lens to understand and treat the source of your eye problem.
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