by Rachel Gore
ost contact-wearers know that it’s not recommended to sleep with contact lenses in, yet a majority of the 45 million people in the U.S. who wear them do it at least once. At the end of a long day or a long night out it can be tempting to jump into bed without bothering to take out your contact lenses: after all, how dangerous can it really be if it’s just one night? As it turns out, very. Here are just some of the negative consequences that can result if you decide to keep your contact lenses in as you head to sleep:
You can develop an eye infection. According to the American Academy of Ophthalmology, sleeping in contact lenses increases your risk for eye infections by six to eight times compared to those who don’t. The average person’s eyes come into contact with bacteria all the time, yet only rarely do eye infections actually occur. This is because a healthy cornea defends your eye from infection-causing contaminants like bacteria.
A cornea needs proper hydration and oxygen to function healthily, and contacts deplete both of those significantly by blocking the surface of your eye. While you’re awake, this isn’t too serious: blinking helps to moisten your eyes and oxygen flows through the tears that you produce. When your eyes are shut as you sleep, though, this no longer happens. Without enough oxygen and moisture, your cornea is less able to fight off bacteria. Untreated eye infections can lead to permanent scarring of your cornea and life-long impacts on your vision.
You might have to stop wearing contacts altogether. When oxygen deprivation is severe, it can lead to the development of a condition called corneal neovascularization (CNV). CNV occurs when new blood vessels grow into avascular corneal tissue due to oxygen deprivation. While increasing the amount of oxygen getting to your cornea can prevent the growth from continuing, these blood vessels will never fully go away. In severe cases, the blood vessels can even block your vision and result in blindness. And even in less serious cases, inflammation may result in your doctor being unable to fit you into lenses anymore.
Another condition that may force you to say good-bye to contact lenses for good is called giant papillary conjunctivitis (GPC), and yes, this can occur as a result of sleeping in your lenses. GPC is an allergic reaction to foreign objects in the eye, such as content lenses, that irritate your upper eyelids and cause small bumps to form. These bumps can pull on your lenses and make them fit poorly. Even if you keep wearing contacts, you can experience uncomfortable symptoms such as red, itchy and swollen eyes, sensitivity to light, watery or pus discharge and excessive movement of your contact lenses. It may also feel like there’s something foreign stuck in your eye or cause swelling, making contacts just too uncomfortable to keep wearing.
You can get eye ulcers. A corneal eye ulcer is an open sore in your eyes or a break in the skin on your cornea. Most of the time, corneal ulcers are caused by an infection or small eye injury, such as erosion on the eye’s surface after wearing contact lenses for too long. Insufficient oxygen allows bacteria to enter the sore or abrasion on your eye’s surface, bind to the cornea, and burrow into your eye. Sleeping with your contacts in and practicing poor hygiene when using contacts are two major causes of eye ulcers in contact lens wearers.
If you get an ulcer, you are likely to experience symptoms such as severe pain, red eye, thick pus drainage, blurred vision and swelling. If you have a large infection, you may be stuck taking prescribed eye drops as frequently as once an hour. You will also be prescribed antibiotics and in severe cases, surgical intervention may be necessary to preserve your vision. While most cases of corneal eye ulcers improve within a few weeks with proper care, untreated ulcers can lead to permanent scarring or blindness.
According to a Centers for Disease Control and Prevention (CDC) report published in 2018, about one in three contact wearers report sleeping or napping in their lenses at some point. The high popularity of contacts may be contributing to the laid-back attitude about using them properly, according to Thomas Steinemann, MD, who co-authored the CDC report: “the average person doesn’t seem to realize the risk that they’re taking by not treating their contact lenses with prescribed care. Patients can sometimes be a little blasé about how they manage their contacts. But they are a medical device inserted into your eye, and you need to listen to your doctor.”
The takeaway message? Take the extra 30 seconds out of your day to remove your contact lenses before sleeping – your eyes will thank you for it by staying healthy.