The eye health risks associated with swimming in your contact lenses depend on the body of water. In all cases, the contact lens provides an environment for microbial colonization, but the risk of infection is much higher in stagnant water than in a chlorinated pool or the ocean. For this reason, contact lenses should never be worn in lakes and rivers, and lenses exposed to this potentially harmful water should be disposed of immediately. The Acanthamoeba organism is especially dangerous and can survive in the space between the contact lens and the eye. Proper lens maintenance reduces the chance of contamination, since protein and lipid buildup provides a site for the microorganism to attach. Once attached to the lens, however, Acanthamoeba is resistant to most disinfecting systems. Acanthamoeba keratitis, or inflammation of the cornea, is almost exclusively associated with contact lens wear in water and can be visually devastating. If you need vision correction while swimming in lakes and rivers, try a pair of prescription swimming goggles.

Pools do not harbor as many microorganisms as lakes and rivers, so the risk of infection is lower. If worn in the pool, contact lenses may absorb chlorine and cause eye irritation. This discomfort is temporary and can be relieved with artificial tears. You may notice that your lenses are difficult to remove after swimming in a pool or taking a shower. Wait at least 30 minutes to allow the water concentration in the lenses to neutralize before removing them. An opposite phenomenon occurs when swimming in the ocean; the high salinity of seawater may cause lenses to float off your eyes. The ocean contains more contaminants than the pool, so close your eyes when you go underwater, or wear swimming goggles. Use UV protected goggles to avoid sun damage. Never swim on beaches with warning signs for contaminated water, and maintain proper lens care to avoid eye infection.

If you are planning to wear your contact lenses in the water, make sure you have an extra pair of lenses, lens solution, and glasses. Swimming goggles are the best way to avoid contamination. If you do expose your lenses to pool or ocean water, disinfect them as soon as possible. Again, if you directly expose your lenses to stagnant water, dispose of them entirely. Daily disposables are a sensible type of lens to use if you are an active swimmer. Rigid gas permeable lenses should not be worn in any kind of water because they are much more likely to float off your eyes than soft contact lenses. Contact your doctor immediately if you experience lasting eye redness, irritation, pain, or sensitivity to light after wearing your contact lenses in water.