Contact lens wearers, brace yourself for a potentially painful read.
See, your eye doctor will warn you not to sleep with contact lenses in, but nearly one-third of contact lens users have done so.
When you wake up, your eyes feel dry, and your lenses must be peeled off your cornea. If you sleep in them just once, you may be okay, but everyone’s affected differently.
Understand this: sleeping in your lenses long-term can result in serious complications.
The cornea is the clear, dome over the top of the eye where light enters to reach the back of the eye. The cornea must be transparent to refract the light and does not have any blood vessels.
The eye, like the rest of the body, relies on oxygen. The cornea gets its oxygen from the air, but with the lid closed overnight, there is no oxygen supply to the cornea. A lens on the eye further reduces the amount of oxygen in the eye.
Corneal hypoxia is a condition where the cornea does not get enough oxygen. It occurs commonly with contact lens users—usually with patients who sleep in their contact lenses. If you wear your contacts all night, your cornea swells. The cornea accumulates lactic acid and pulls water into it resulting in swelling, also called edema.
The signs of corneal hypoxia are blurred vision, burning, eye irritation, excessive tearing or even swelling of the outer layer of the cornea. Corneal hypoxia can be reversed when the eye receives normal levels of oxygen, but it can also result in permanent changes to the corneal endothelium. If you avoid sleeping in your lenses, you are unlikely to have corneal hypoxia.
Your doctor may ask you to take an extended break from contact lens wear, treat your eyes with a steroid eye drop, or consider switching to daily lenses or new lens technology. Newer lenses are made from silicone, a material that allows more oxygen to pass through and reach the cornea.
Warpage of the cornea is a serious consequence of sleeping with contact lenses. If your corneas are warped, you may not be able to have LASIK surgery. Overwearing your lenses causes changes in the epithelial cells of the eye, remodeling, and thickening of the layers of the cornea.
It can take the cornea up to a week to resolve, but many surgeons will want you to wait years before a surgical evaluation.
Your prescription can change, your vision may become blurry and there may be permanent changes in the shape of your cornea if you sleep in your lenses.
When you sleep in contacts, the risk of infection increases enormously.
The most common infection from contact lenses is called microbial (bacterial) keratitis. Bacterial keratitis is a corneal eye infection that is often caused by the bacteria Pseudomonas Aeruginosa (in contact lens wearers) or Staphylococcus Aureus.
Sleeping in your lenses creates an environment for bacteria to grow. If you do have a bacterial infection, you will need to be treated with anti-bacterial drops. Severe corneal infections may require surgery, and result in damage and permanent vision loss.
Blurry vision, redness, pain, tearing, and light sensitivity are the most common symptoms of keratitis. You may also feel like something is in your eye. Most red eyes diagnosed as “pink eye” are not pink eye but are most likely an infection from over-wearing your contacts.
Regardless of the lens material and the frequency of sleeping in your lenses, sleeping in contact lenses is a risk factor for bacterial keratitis. Even though some lenses are approved by the FDA for overnight wear, they acknowledge there is a risk of an infection.
Search “giant papillary conjunctivitis” and you’ll never sleep with your lenses in again.
An allergy of the eyelid is called giant papillary conjunctivitis or GPC, which results in medium to large bumps inside the upper eyelid. If you have GPC, your lenses can seem to move around on your eyes and your eye may be more uncomfortable with your lenses out than with them in.
When the lenses are in, the contact acts like a bandage for the cornea, but once removed, the bumps on the lid rub against your cornea causing irritation and discomfort.
Your eye doctor will make a GPC diagnosis by flipping your lid and looking underneath. GPC occurs because the lens gets old, dirty, and protein builds up on the outside of the lens. Your eyelid becomes irritated when it rubs up against a dirty lens all day and all night. Wearing your lenses for extended periods like overnight or not changing your lenses as you should are common causes of GPC.
A corneal ulcer is a common occurrence after sleeping in a contact lens.
An ulcer is a defect in the top layer of the cornea, called the epithelium and on the second layer, called the stroma. If you sleep in your lenses, and wake up with eye pain, blurry vision, and extreme light sensitivity, you may have an ulcer.
An ulcer is visible on the eye as a white, fluffy area. And if left untreated, it could become an open sore that may scar. A doctor will recommend staying out of your lenses for several days and will prescribe an antibiotic or antibiotic/steroid combination. Scars from a history of corneal ulcers can also prohibit you from being a candidate for LASIK surgery.
Wear your contacts safely
Contact lenses are safe if you change them as recommended, clean them with the appropriate solutions, and remove them each night.