Topic Overview

To avoid eye problems, be sure to follow the directions for cleaning and wearing contact lenses. Contact lens wearers have an increased risk for serious eye infections and injury to the cornea. Contact lenses can cause eye problems, such as damage to the cornea or eye infections. Small objects that get into the eye may become trapped under a lens and scratch the cornea. Pinkeye (conjunctivitis) or other minor eye infections are likely to irritate your eyes and make wearing contacts uncomfortable and unsafe.

Symptoms of possible problems with contacts include redness, pain or burning in the eye, drainage, blurred vision, or sensitivity to light (photophobia). If you are having problems, remove your lenses and disinfect them. If you have symptoms longer than 2 to 3 hours after removing and cleaning your contacts, call your eye doctor.

Soft lenses

• Daily-wear lenses are removed and cleaned at night and reinserted in the morning. They take less time to get used to than hard lenses, but they are less durable.
• Extended-wear lenses can be worn for up to a week at a time, day and night. They are then removed, cleaned, and reinserted. But some people cannot tolerate the extended wear. Their eyes become irritated if the contacts are not regularly removed and cleaned. Extended use may be uncomfortable, and it increases the risk of damaging the eye. Many eye doctors (ophthalmologists) recommend that you take your contacts out while you sleep.
• Disposable lenses (daily and extended-wear) were designed to be worn for up to several weeks and then discarded. Many new contact lens wearers now choose disposable lenses. Disposable lenses were introduced because it was thought that replacing lenses more often would reduce the risks of infection of the cornea (infectious or bacterial keratitis), a dangerous complication of soft lenses. But later studies have shown that people who wear disposable lenses, especially the extended-wear kind, may have a higher risk of keratitis.

Hard lenses

• Conventional hard lenses (PMMA) are made of a stiff plastic (polymethyl methacrylate, or PMMA), which does not mold to the shape of the eye. These lenses correct vision with no distortion, and they are durable. But they are the least comfortable type of contact lens. Because they reduce the amount of oxygen reaching the cornea, people who wear them are at risk of overwearing syndrome and other problems.
• Rigid gas-permeable (RGP) lenses are somewhat less durable, but they are more comfortable than conventional hard lenses. Some gas-permeable lenses are designed for extended wear (overnight, up to 7 days). But many eye specialists advise against wearing them for the extended period, because there is a small risk of severe infection.

Safety tips and lens care

The following tips can help you keep your contacts clean and safe, which will help keep your eyes healthy and your vision as clear as possible.

• Carefully follow the cleaning instructions for your lenses. Keep your lenses and all supplies very clean. Always wash and rinse your hands thoroughly before inserting or removing lenses. Do not apply hand lotion before handling your contacts.
• Use the lens care system your eye specialist recommends. Do not mix products, because they may not be compatible. Never use homemade saline solutions. (They can be easily contaminated with bacteria.) Do not reuse solution.
• Never wet your lenses with saliva or place lenses in your mouth. The bacteria that are naturally present in your mouth may cause an eye infection.
• Always rinse the lens storage case and let it air-dry to avoid contamination. Never use tap water to rinse or store your lenses.
• Visit your eye doctor once a year to check the condition of your lenses and the health of your eyes.
• Contact lenses, especially soft lenses, may absorb eyedrops, which can cause problems. If you use eye medicines, leave your lenses out for about 30 minutes after using the eyedrops.
• Insert your lenses before applying makeup. Take care not to get makeup on the lenses. Replace eye makeup (especially mascara) every 3 to 6 months to reduce the risk of contamination. Do not apply makeup to the inner rim of the eyelid.
• Decorative colour lenses can cause eye problems, such as damage to the cornea or eye infections, just as easily as contact lenses worn for vision correction. To avoid eye problems, be sure to follow the directions for cleaning and wearing these lenses.