Eye care professionals strongly recommend avoiding swimming while wearing contact lenses. This caution applies universally to all water environments, including pools, oceans, lakes, and hot tubs. Wearing lenses while swimming significantly increases the risk of eye infection, irritation, and physical damage to the cornea.
The Hazards of Water Exposure
Soft contact lenses are hydrophilic and absorb moisture. They act like sponges, soaking up water and trapping chemicals or harmful microorganisms against the eye’s surface. This contaminated barrier prevents the eye’s natural tear film from washing away foreign particles.
Water exposure can also physically compromise the lens and eye surface. The lens material may absorb water and change shape, causing it to tighten and adhere firmly to the cornea. This adherence makes the lens difficult to remove and can cause micro-abrasions on the delicate corneal surface.
Chemicals in water sources introduce another risk, particularly in treated water like swimming pools. Chlorine and other disinfectants are absorbed by the lens material, leading to irritation, redness, and severe dry eye once the lens dehydrates. Saltwater can similarly cause dryness and discomfort, exacerbated by the lens trapping irritants.
Understanding the Risks of Eye Infection
The most serious medical consequence of swimming with contacts is the potential for a severe parasitic infection known as Acanthamoeba keratitis (AK). This rare but aggressive infection is caused by a protozoan found in tap water, lakes, rivers, and swimming pools. The contact lens creates an environment for the parasite to adhere to and multiply on the eye’s surface.
When the lens causes microscopic scratches on the cornea, the Acanthamoeba parasite can enter the deeper tissue, resulting in a painful and challenging infection. AK frequently requires months of intensive treatment and can lead to permanent vision impairment or the need for a corneal transplant. Swimming with lenses also increases the risk of more common bacterial and fungal infections that can lead to corneal ulcers.
Symptoms that require immediate medical attention after lens exposure to water include pronounced eye pain, abnormal redness, increased light sensitivity, and noticeably blurry vision. These signs indicate that a serious infection or corneal injury may be developing and should not be disregarded.
Safer Options for Water Activities
The safest measure for vision correction while participating in water activities is to use prescription swimming goggles. These are custom-made to match an individual’s vision correction needs and create a watertight seal, eliminating the risk of water contact with the eyes. They are the preferred option for regular swimmers who require clear underwater vision.
If wearing contacts is unavoidable, the only acceptable alternative is to use a fresh pair of daily disposable lenses paired with tight-fitting, waterproof goggles. The daily disposables must be removed and discarded immediately upon exiting the water to prevent any trapped contaminants from remaining on the eye. They should never be cleaned and stored for later use.
Extended-wear or multi-use contact lenses should never be worn while swimming, as the risk of contamination and subsequent infection is significantly higher. The potential for a sight-threatening infection outweighs the convenience of clear vision for a short period. Always have a pair of glasses or fresh daily lenses ready for use immediately after drying off.