Sleeping with your contacts in is not recommended. In fact, it can endanger your eye health and even your vision.
We get it: It’s bedtime after a long day. Everything is ready for a restful night of sleep. You’ve brushed your teeth, you’re wearing comfortable pajamas, you’re under a cozy blanket, you’re dozing off, and just as you close your eyes, you remember that you’re still wearing your contact lenses.
No one likes to get out of bed once they’ve settled in for the night. Approximately one-third of contact lens wearers say they’ve slept in their contacts before. So, you’d be forgiven for asking, “Is it bad to sleep with contacts in?”
But study after study has confirmed that sleeping with contacts in can put your eye health at risk. Just remember that contact lenses are medical devices and should only be used according to your eye doctor’s directions.
Read on to learn why it’s always best to take your contacts out before bed and what can happen if you don’t.
What Happens if You Sleep With Contacts In?
Sleeping with contacts in your eyes substantially raises the risk of eye infection, in particular microbial keratitis. Microbial keratitis is inflammation and infection of the cornea (the protective dome on the surface of your eye, exactly where your contact lens sits).
This condition is commonly caused by bacteria, but it can also be viral, fungal, or parasitic. Left untreated, it can have very serious complications, even resulting in vision loss and permanent scarring of the eye which can cause blindness.
One study showed that wearing contacts overnight increased the relative risk of microbial keratitis by more than five times—regardless of the type of contact lens used. Additionally, the CDC reports that sleeping in contacts can up your risk of acquiring an infection by six to eight times. We really don’t like those odds!
Symptoms of Keratitis
- Red eyes
- Irritation or itchiness in or around the eyes
- Watery eyes or notable discharge from the eyes
- Pain in or around the eyes
- Sensitivity to light
- Blurred vision
If you’re experiencing any of the above symptoms after snoozing with your lenses in, you may have gotten an eye infection from sleeping in contacts. But the only way to be sure is to see an optometrist—book an eye exam ASAP.
Other Dangers of Sleeping With Contacts In
When you sleep with your contacts in, microbial keratitis isn’t the only eye condition you have to worry about. You’re also at risk for conjunctivitis (commonly known as pink eye), corneal ulcers, and corneal hypoxia (a condition that occurs when the cornea doesn’t get enough oxygen).
If you manage to avoid any of the above, you still might wake up with general inflammation and irritation. Dry, sore, or red eyes are common consequences of sleeping in your contact lenses. Plus, if there’s any debris trapped under them, you’ll be exposing your eyes to it all night, potentially causing more damage.
Several news reports have documented the distressing results of sleeping with contact lenses in, and the CDC also presented six case studies in 2018 that illustrate the importance of taking your contacts out before bed. A content warning: These links may contain graphic images.
Can You Go Blind From Sleeping With Contacts In?
In severe cases, an infection caused by sleeping with contacts in can result in vision loss. And, yes, if you don’t seek treatment, you can go blind in the affected eye. You might also require surgery or never fully regain your original visual acuity. Also, sleeping in contacts may cause changes to your eyes that may not allow you to continue to wear contacts.
Why Does Sleeping With Contacts Cause Problems?
Sleeping with contacts in makes it easier for germs to gain a foothold on the surface of your eye. Scientists are still researching why exactly this might be the case.
Lack of Oxygen to the Cornea
For a while, it was thought that wearing contacts while sleeping might lead to infection because the lenses limited the cornea’s exposure to oxygen. However, as lens designs have improved and allowed more and more oxygen through to the eye, the risk of infection has not declined as expected.
This finding doesn’t mean that lack of oxygen (hypoxia) isn’t contributing to infections—using the most breathable contact lenses does seem to reduce the severity of the infection you get—but it does mean it’s not the whole story.
Stagnation of the Tear Film
One hypothesis is that sleeping in contact lenses causes stagnation of the tear film. When you’re not wearing contacts, the tear film that covers the surface of your eye protects it from bacteria and debris. When you blink, you’re sort of “refreshing” the tear film: Adding new fluid and clearing out some of the old.
Because contact lenses sit over the tear film, they can inhibit this tear exchange. And when your eyes are closed as you sleep—i.e., not blinking at all—your tear film really can’t perform its protective function to the fullest. Germs don’t get washed away and instead have time to spread. The longer you sleep in your contacts, the more opportunity you’re giving them to cause infection.
Interaction With the Surface of the Eye
Another factor could be that prolonged contact lens wear affects the physical structure of your eye’s surface. Studies show that the ocular surface environment is extraordinarily sensitive and can even change shape if subjected to the pressure of your contact lenses for too long. Researchers are investigating how these surface interactions can hasten infection.
Additionally, your lenses might rub uncomfortably against the cornea as you sleep, upping the chance of scratches and irritation.
Exposure to Microbes via Contamination
Your contact lenses can transfer germs to your eyes from other sources, including your hands or your lens case. Sleeping in your contact lenses gives these germs an environment where it’s easier to thrive.
That’s why it’s so important to wash your hands, let your contact case air dry during the day, regularly clean your contact case, always use fresh contact solution for storage, and clean your contact lenses thoroughly with each use. If your contact lens hygiene isn’t up to snuff, sleeping in your lenses will only compound the consequences!
With daily contacts, on the other hand, you simply toss your lenses out at the end of the day and grab a fresh pair to wear each morning. Because of this, daily disposable contact lenses are considered a more hygienic option, which is why they’re the most recommended type of contacts by eye doctors.
How Long Can You Sleep With Contacts In?
There’s no safe amount of time that you can sleep with your contacts in your eyes. Optometrists and ophthalmologists everywhere will recommend against it entirely—why risk any complications?
Can You Sleep With Contacts in for One Night?
Even one night of sleeping with contacts in can cause irritated eyes and other symptoms. Although the most serious infections often correlate with repeated and regular nightly wear, you should always take your contacts out before bed. Even sleeping in your contacts for one night can cause a serious infection.
Can You Sleep With Contacts in for One Hour?
It’s best not to sleep in contacts at all—even for an hour or so. Every time you snooze with your contacts in, your risk of infection goes up. If you’re feeling drowsy, the safest thing to do is take your contacts out as a precaution.
Can You Take a Nap With Contacts In?
Eye doctors advise against napping with your contacts in. Yes, even if the nap is shorter than an hour, it can still increase the chances of irritation and infection in your eyes. You’ll also probably wake up with “sticky” or dry eyes, and no one wants that!
Just remember: Whether you sleep in your contacts for one night, for one hour, or for a few minutes, you are increasing your risk of a severe infection, which can cause vision loss or blindness.