About 41 million people in the U.S. wear contact lenses and almost all of them practice at least one risky behavior while wearing them, cleaning them, or storing them, according to the Centers for Disease Control. Risky behaviors to avoid include topping off or re-using contact solution instead of replacing it, using the same case or lenses for too long, and sleeping, showering, and swimming in contact lenses.
For many people who wear them regularly, contacts become so much a part of daily life, that it can be easy to forget lenses are medical devices and can pose risks. In fact, the U.S. Food and Drug Administration (FDA) reported more than 1,000 serious eye infections in contact lens wearers during the past 10 years. Almost 20 percent of these infections resulted in some degree of vision loss or corneal scarring, or required a corneal transplant.
About 1 million corneal infections—such as keratitis—are reported each year in the U.S. and contact lenses are the primary risk factor for these infections. According to researchers, sleeping in contacts increases infection risk by about 7 percent and wearing the same pair of lenses longer than recommended is associated with an increased risk of 8 percent. According to Thomas Steinemann, clinical spokesman for the American Academy of Ophthalmology, contact lenses should not be worn to sleep—even if they are approved for extended or continuous wear.
Earlier studies indicate that only about 2 percent of regular contact wearers consistently follow recommendations for using them safely. Experts also warn that lenses should be purchased exclusively through an eye care professional and caution against wearing “costume” contact lenses. When used correctly, contacts are a safe and convenient way to improve vision, when used incorrectly, however, they can put your eyesight at risk.