Why Water and Contact Lenses Don’t Mix
The golden rule of contact lens care is to keep them away from water. This includes tap water, swimming pools, oceans, lakes, hot tubs, and even the shower. While tap water is treated to be safe for drinking, it is not sterile and contains microorganisms.
One of the most dangerous is an amoeba called Acanthamoeba, which is commonly found in various water sources. This organism can cause Acanthamoeba keratitis, a rare but severe and painful eye infection that can be difficult to treat and may lead to vision loss or even blindness. When a contact lens is exposed to water, it can change shape, swell, and stick to the eye, trapping these microbes against your cornea and making it easier for an infection to take hold.
Showering, Swimming, and Hot Tubs
It may seem harmless, but health experts universally advise against wearing contact lenses while showering, swimming, or using a hot tub. Water can get trapped behind the lens, creating an ideal environment for harmful bacteria to grow. Even chlorinated pools are not risk-free; chlorine doesn't kill all germs and can also disrupt your eye's natural tear film, causing irritation. Hot tubs are particularly risky because the warm water is a perfect breeding ground for microbes. If you accidentally expose your lenses to water, the safest course of action is to remove them as soon as possible. Daily disposables should be thrown away, while other lenses should be thoroughly cleaned and disinfected overnight before re-wearing.
Your Lens Case: A Potential Breeding Ground
Proper lens care extends beyond the lenses themselves; your storage case is a critical component of eye health. A dirty or damp case can become a source of contamination. Bacteria can multiply in the wells of the case and form a 'biofilm', a slimy, protective layer that is resistant to disinfecting solutions. When you place your lenses in a contaminated case, you are essentially transferring those germs directly to your eyes the next morning. This is why simply 'topping off' old solution with a bit of fresh solution is a dangerous habit; it dilutes the disinfectant's power and allows bacteria to thrive.
The Correct Way to Clean and Dry Your Case
Keeping your case clean is a simple, daily habit. First, after putting in your lenses, dump out all of the old solution. Next, rinse the case thoroughly—including the lids—with fresh contact lens solution, never tap water. You can use a clean finger to gently rub the inside of the case wells to dislodge any buildup before rinsing again. Finally, and perhaps most importantly, let the case air-dry completely. Leave the case and its caps open and placed upside down on a clean tissue. A moist environment encourages germ growth, so ensuring the case is fully dry is crucial.
When to Replace Your Contact Lens Case
Even with diligent cleaning, your contact lens case should be replaced regularly. The standard recommendation from most eye care professionals and the CDC is to get a new case at least every three months. Over time, microscopic cracks can form in the plastic, creating hiding spots for bacteria that even thorough cleaning can't reach. A good habit is to discard your old case each time you open a new bottle of multipurpose solution, as many come with a new case included. If you notice any visible cracks, discoloration, or a persistent film, replace the case immediately, even if it has not been three months.
