The switch from glasses to contact lenses comes with several perks, such as having clear peripheral vision. However, unlike glasses, you can't easily slide them on and off, or throw them on the bedside table at night before you sleep; they require proper care. The single best way to prevent eye infections is to avoid the most common mistakes contact lens users make, from sleeping in them to wearing them past their expiration date.

Previous studies have found that more than 99 percent of people who wear contact lenses are guilty of at least one risky behavior that can set the stage for serious eye infections. These behaviors are so common because people can get away with them several times before something bad happens.

Read on about these common mistakes and why it's important for you to avoid them too.

Sleeping In Your Contacts

Several manufacturers will claim there are lenses that are much safer to sleep in than others — referred to as "extended wear.” Users will start to fall into the habit of sleeping with their contacts on, and wake up with dry eyes, and blurry vision. However, a recent report by the Centers for Disease Control and Prevention found 25 percent of eye infections are due to modifiable risk factors, “including occasionally sleeping in contacts or wearing them for long periods of time, whereas few reports were associated with problems with the contact lens itself, such as the lens being ripped or torn.”

Extended wear deprives the cornea — the outside layer of the eye that the contacts cover — from oxygen. Overnight wear will likely lead to irritation and discomfort, and at worst — a serious infection. A 2009 study published in the Journal of Optometry found sleeping in contacts was the probable main cause of microbial keratitis.

Taking A Shower Or A Swim In Your Contacts

Swimming and showering in your contacts seems like a harmless habit, but most water sources can actually irritate your eyes. In the recent CDC report, researchers found lenses are susceptible to absorbing water, and can swell with the impurities and microorganisms found in the tap, which can change the lens shape entirely. In addition, most water sources include the microorganism Acanthamoeba, which can cause an extremely painful infection and potentially lead to blindness.

The same 2009 study found contact lenses account for 95 percent of acanthamoeba eye infections. This is because the acanthamoeba is drawn to the contact lenses. Bacteria living on the surface of the contact can serve as a food source for the acanthamoeba, allowing it to survive in the eye.

Using Tap Water To Clean Your Contacts

Showering, swimming, and even using tap water to clean your contacts can lead to serious eye damage. Tap water may be pure enough to drink, but it's not sterile. Acanthamoeba can live in tap water, therefore, soaking your lenses in water from the sink can lead to eye infections. Avoiding this will prevent the cornea from getting inflamed, or scarred, which can impair vision. This also applies to filtered water from the sink because bacteria can grow on the faucet, and enter the water, to get on your lenses.

Wearing Your Contacts Past The Expiration Date

You probably think you're getting more bang for your buck by using old contacts, but this can lead to expensive medical bills later on. Old lenses become coated with germs and the build-up of solution, proteins, and other residues. This makes lenses uncomfortable to wear, and can lead to infection.

A 2008 study published in the The South African Optometrist found there was some contamination in expired lens packages, but they were unable to make any broad claims due to a very small sample size. However, doctors from the American Academy of Ophthalmology and the American Optometric Association have confirmed solution containing the lenses can go bad, because it can become more acidic and more alkaline (basic). Therefore, with an unstable pH (acidity) can lead to extreme discomfort and irritability, and possibly eye damage.

Not Replacing Your Contacts Case

Contact lens cases should be cleaned thoroughly with solution every day, and replaced at least every three months, according to the The American Optometric Association. Using an old case can lead to germs growing on the case and on the lens. A 2012 study published in the journal Ophthalmology showed the risk of eye infection was 6.4 times greater in those who didn't properly clean their contact cases, and 5.4 times greater in those who didn’t replace their cases frequently enough. The best thing to do is replace your contacts cases as recommended.

Avoid making these 5 common contact lens mistakes for better eye health.