Wearing contact lenses while showering is common, but eye care professionals strongly advise against exposing contacts to any form of water, including tap water. The water flowing from a showerhead contains microscopic organisms and chemical properties that pose a direct threat to the sensitive surface of the eye. Understanding these specific risks is important for maintaining vision and avoiding serious complications.
The Specific Biological Threat in Water
The primary biological concern with water exposure is the presence of the microscopic parasite Acanthamoeba. This organism is ubiquitous, existing naturally in various water sources, including tap water, pools, and hot tubs. While harmless if ingested, Acanthamoeba can cause a severe, sight-threatening eye infection called Acanthamoeba keratitis when it contacts the cornea. The contact lens traps the parasite directly against the corneal tissue, creating an ideal environment for infection.
Infection occurs when the amoeba invades the corneal stroma, causing intense inflammation and tissue destruction. This infection is difficult to treat because the parasite forms a resistant, dormant cyst stage impervious to many standard antimicrobial treatments. Treatment is often lengthy, and severe cases may necessitate a cornea transplant or lead to permanent vision loss.
How Water Physically Affects Contact Lenses
Beyond biological dangers, water physically alters the structure of soft contact lenses, which are typically made of hydrogel materials. Contact lens solutions are formulated to be isotonic, matching the natural salinity and pH of tears to maintain the lens’s proper shape and fit. Tap water is a hypotonic solution, meaning it has a much lower salt concentration than the lens and the eye.
When a soft lens is exposed to hypotonic water, it acts like a sponge, rapidly absorbing water and causing it to swell and change shape. This swelling can cause the lens to tighten and adhere more firmly to the eye’s surface, trapping debris and microorganisms underneath. The altered fit can also lead to micro-abrasions on the corneal epithelium, creating easy entry points for infection. Furthermore, tap water contains minerals like calcium and magnesium, which bind to the lens material, leading to deposits that increase irritation and reduce visual clarity.
Recognizing the Signs of Eye Infection
Knowing the symptoms of a corneal infection is important for contact lens wearers, especially following water exposure. A common sign is eye redness that persists even after the contact lens has been removed. Affected individuals often experience severe, disproportionate eye pain that seems excessive for simple irritation. This pain is often accompanied by a persistent feeling that something is stuck in the eye, which washing or blinking does not resolve.
Other symptoms include excessive tearing and increased sensitivity to light (photophobia). Vision may also become noticeably blurred or hazy as the infection progresses. If any of these symptoms develop, immediate consultation with an eye care professional is strongly advised, as early diagnosis is crucial for preventing severe, quickly progressing infections.
Safe Habits and Emergency Action Steps
The most effective way to prevent water-related eye infections is to remove contact lenses before engaging in any water activities, including showering, swimming, or using a hot tub. Always use only commercially manufactured, sterile contact lens solutions for rinsing, cleaning, and storing your lenses. Never use tap water or bottled water as a substitute for contact solution, including when rinsing your storage case. The lens case should be cleaned with solution, wiped with a clean tissue, and allowed to air-dry upside down after each use to minimize microbial growth.
If accidental water exposure occurs while wearing lenses, swift action is necessary. Remove the lenses immediately using clean, dry hands. If you wear daily disposable lenses, discard that pair right away. For reusable lenses, they must be thoroughly cleaned and disinfected by rubbing, rinsing, and soaking them in a fresh, disinfecting solution for the full recommended duration. If any irritation, redness, or discomfort persists, schedule an urgent appointment with your eye care provider.