Wearing contact lenses while swimming—in pools, oceans, lakes, or hot tubs—is strongly discouraged by eye care professionals. Water exposure significantly increases the risk of eye irritation, discomfort, and potentially serious infection. Both the Federal Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC) specifically advise against wearing contact lenses during any water activity. This advice protects the health of the cornea and prevents vision-threatening complications.
Why Water and Contacts Don’t Mix
Soft contact lenses are made from porous, gel-like materials called hydrogels designed to absorb and retain moisture. While this characteristic makes them comfortable, it also makes them vulnerable in water environments. When exposed to external water, the lens material acts like a sponge, soaking up water from the pool or ocean.
The absorption of non-sterile water causes the lens to swell and change shape, leading to an improper fit on the eye. This distortion blurs vision and can cause the lens to adhere too tightly to the cornea or fold onto itself, making removal difficult. Water exposure also introduces chemical irritants, such as chlorine, which bind to the lens and cause dryness, inflammation, and a burning sensation.
The physical presence of the lens under these conditions can lead to mechanical damage. A poorly fitting or misshapen lens can trap debris or small particles between the lens and the eye’s surface. This trapped material rubs against the cornea, potentially causing painful corneal abrasions or micro-scratches. These tiny breaks in the corneal surface provide an easy entry point for harmful microorganisms.
The Primary Infection Risk
The most significant danger of wearing contacts while swimming is introducing pathogens directly to the eye’s surface. All natural and treated water sources, including tap water, pools, and lakes, harbor bacteria, fungi, and microscopic parasites. The soft lens holds these microbes in direct, prolonged contact with the cornea, greatly increasing the risk of infection.
One particularly concerning threat is Acanthamoeba keratitis (AK), a rare but vision-threatening parasitic infection. The Acanthamoeba parasite is commonly found in various water environments and has a strong affinity for adhering to contact lenses. Wearing lenses in water is the primary risk factor for contracting this infection.
Even in treated swimming pools, standard disinfectants like chlorine are often insufficient to eliminate hardier organisms such as Acanthamoeba. The environment under the lens provides a sheltered space where these microbes can thrive and infect the cornea. Acanthamoeba keratitis is notoriously difficult to treat, often requiring months or even years of therapy. Untreated or severe cases can lead to corneal scarring, significant vision loss, or blindness.
Safe Alternatives for Vision Correction
For individuals requiring vision correction to swim safely, the best alternative is prescription swimming goggles. These goggles are waterproof and feature corrective lenses customized to the wearer’s prescription, providing clear underwater vision without eye exposure to water. Prescription goggles are available for common refractive errors like myopia, hyperopia, and astigmatism.
Another viable alternative is Orthokeratology (Ortho-K), which involves wearing specialized rigid contact lenses overnight. These lenses temporarily reshape the cornea, allowing for clear vision throughout the day without the need for corrective eyewear during water activities. This option eliminates the risk associated with lens exposure to water while swimming.
If a person must wear contact lenses while swimming, they should wear a pair of well-fitting, tight, waterproof swimming goggles over the lenses to minimize water exposure. In this scenario, daily disposable contact lenses are the preferred choice. They must be removed and discarded immediately after swimming, even if the lenses feel fine. Immediate disposal is the safest course of action for reusable lenses exposed to water, though they must be removed and disinfected overnight in fresh solution before potential re-use.