Eye care professionals and the Food and Drug Administration (FDA) strongly advise against wearing contact lenses during any water activity. This warning applies universally to all water sources, including tap water, swimming pools, hot tubs, lakes, and oceans. The health risks are severe, ranging from immediate discomfort and lens damage to potentially permanent vision loss due to infection. Contact lens wearers should consider water exposure a firm contraindication for lens use.
Why Water and Lenses Don’t Mix
The primary issue with water exposure is the physical and chemical reaction that occurs with soft contact lens materials, which are typically hydrogels. These lenses are designed to absorb and maintain a specific water content, and exposure to non-sterile water upsets this delicate balance. Fresh water, which is hypotonic compared to natural tears, causes the lens material to rapidly absorb the external water.
This sudden absorption makes the soft lens swell and significantly change its shape, leading to a distorted fit on the cornea. A lens that no longer fits properly can cause blurred vision and intense irritation. Swelling can also cause the lens to adhere tightly to the corneal surface, increasing the risk of a painful corneal abrasion when the lens is removed.
Chlorine and other chemicals in pool water can bind directly to the porous lens material, further altering the lens structure and exacerbating eye irritation. Even rigid gas permeable (RGP) lenses are unsafe, as they can trap contaminated water against the corneal surface, creating a reservoir of irritants and microbes.
The Threat of Waterborne Microbes
The most serious danger of wearing contact lenses underwater is the risk of developing microbial keratitis, a severe eye infection. Water, regardless of whether it is chlorinated pool water or natural lake water, is not sterile and harbors numerous pathogens. The soft, porous nature of a contact lens acts like a sponge, soaking up these microorganisms and trapping them against the eye’s cornea.
A specific danger is exposure to Acanthamoeba, a microscopic, cyst-forming organism commonly found in all water sources, including tap water. If this amoeba adheres to a contact lens, it can penetrate the corneal tissue, causing Acanthamoeba keratitis. This infection is difficult to treat because the amoeba is highly resistant to many disinfectants and can survive in a dormant cyst phase.
Acanthamoeba keratitis can result in excruciating pain, significant vision impairment, and, in some cases, permanent vision loss or the need for a corneal transplant. The lens itself can create microscopic abrasions on the cornea, making it easier for the organism to invade the eye’s surface. Eye care professionals emphasize complete avoidance of water contact while wearing lenses, as even brief exposure can introduce the pathogen.
Emergency Steps If Contact Occurs
If water accidentally gets into your eyes while wearing contacts, immediate action is necessary to minimize the potential health risk. The first step is to remove the lenses as soon as possible, using clean and thoroughly dried hands. Do not rub the eye or attempt to wipe the water away while the lens is still in place.
If the lenses are daily disposables, they must be discarded immediately and replaced with a fresh pair once your eyes feel normal. Reusable lenses must undergo a full cleaning and disinfection cycle with fresh, sterile contact lens solution for the minimum recommended time. Never rinse the lenses or the lens case with tap water, as this only reintroduces the microbial threat.
Monitor your eyes closely for any developing symptoms that could indicate an infection. Signs such as persistent redness, eye pain, excessive tearing, light sensitivity (photophobia), or a gritty sensation require an immediate visit to an eye care professional. Early diagnosis is essential for managing waterborne infections.
Vision Options for Water Activities
For individuals who require vision correction to safely enjoy water activities, several alternatives eliminate the need to wear contacts in water. The safest and most recommended option is the use of prescription swim goggles or a prescription diving mask. These items are customized to match your exact vision parameters, providing clear sight without the risks associated with water-to-lens contact.
Alternatively, Orthokeratology (Ortho-K) can provide temporary freedom from corrective lenses during the day. Ortho-K involves wearing specialized rigid lenses overnight to gently reshape the cornea, allowing for clear vision during the day without wearing any lenses, including during swimming. If prescription eyewear is not available, wearing well-sealed, non-prescription goggles over a new pair of daily disposable contacts can serve as a protective barrier. However, the lenses should still be removed and discarded immediately after swimming.