Why You Should Never Use Tap Water on Contact Lenses
The Hidden Dangers in Tap Water
Acanthamoeba is a tiny organism that can be present in tap water, lakes, and even well-maintained water systems. This amoeba feeds on bacteria and thrives in many water sources we use every day. When it comes into contact with your contact lenses, it can attach to the lens surface and then transfer to your eye.
Once Acanthamoeba reaches the cornea, it can burrow into the tissue and cause a severe infection. These organisms can adhere to contact lenses and thrive in lens cases and biofilms, where they become trapped against the cornea during lens wear.
Your tap water may look clean, but it can contain many types of bacteria and fungi. Pseudomonas aeruginosa is one of the most common bacteria found in water supplies and can cause rapid eye infections. Other bacteria like Staphylococcus and Streptococcus species also live in plumbing systems and water fixtures.
- Pseudomonas bacteria can damage your cornea within 24 hours
- Fungi grow in pipes, shower heads, and faucet aerators
- Biofilms in plumbing harbor many different microorganisms
- Even treated municipal water contains low levels of bacteria
Tap water contains chlorine, fluoride, and other chemicals used to make it safe to drink. These substances can bind to the material of your contact lenses and create rough spots or deposits. The lenses may also absorb minerals like calcium and magnesium.
When your lenses change shape or develop deposits, they no longer fit properly on your eye. This poor fit can scratch your cornea and create tiny openings where microorganisms can enter. Hypotonic tap water can also cause soft contact lenses to swell abnormally, further disrupting fit and potentially compromising the corneal surface.
Many people think that filtering or boiling water makes it safe for contact lenses, but this is not true. Home water filters remove some contaminants but do not eliminate Acanthamoeba cysts, which have hard protective shells. Boiling water kills most bacteria but does not remove mineral deposits or chemical residues.
- Acanthamoeba cysts can resist many home filtration systems, which are not validated for contact lens sterility
- Boiled water still contains minerals that damage lenses
- Cooled boiled water is not sterile, can be recontaminated, and is not an isotonic disinfecting solution designed for lenses
- Filtered water may still contain microorganisms and is not validated for sterility
- Only use products specifically labeled for contact lens disinfection and storage
Eye Infections Caused by Tap Water Exposure
Eye infections from tap water exposure can start with mild symptoms that quickly become severe. You might first notice that your eyes feel scratchy or uncomfortable when you wear your lenses. Redness and increased tearing are often the earliest signs that something is wrong.
As an infection develops, you may experience blurred vision, pain, and sensitivity to light. Any discharge from your eyes, whether clear, white, or colored, should prompt immediate attention. We urge you to remove your contacts right away if you notice any of these symptoms.
Acanthamoeba keratitis is a rare but devastating infection of the cornea. This condition is extremely painful and difficult to treat because the amoeba forms cysts that resist standard medications. Water exposure is a well-recognized risk factor in contact lens wearers.
- Symptoms often include severe eye pain and light sensitivity
- The infection can mimic other conditions, delaying diagnosis
- Treatment may take months and require multiple medications
- Permanent vision loss can occur even with aggressive treatment
- Some patients eventually need corneal transplant surgery
Bacterial keratitis occurs when bacteria infect your cornea, creating an open sore or ulcer. Tap water exposure is a common cause because the bacteria adhere to contact lenses and then transfer to your eye. Pseudomonas bacteria are particularly aggressive and can penetrate deep into corneal tissue.
Corneal ulcers may appear as a white or gray spot, but are often not visible without an exam. Without prompt treatment, the infection can spread and create scarring. We often see patients who waited too long to seek help and developed permanent vision problems as a result.
Infections from tap water can scar your cornea, which is the clear front window of your eye. Corneal scars block and scatter light, making your vision permanently blurry or distorted. Deep infections can also damage the inner layers of the cornea, affecting its ability to stay clear.
In severe cases, the infection may spread to other parts of the eye or cause the cornea to perforate. We may recommend emergency surgery to save the eye and prevent total vision loss. Even after successful treatment, many patients need glasses or special contact lenses to see clearly again.
If tap water touches your contact lenses, remove them immediately and follow proper cleaning or disposal steps. If you develop any eye discomfort after water exposure, contact our office the same day. Contact lens wearers with a painful red eye, light sensitivity, or decreased vision need same-day urgent evaluation. Do not wait to see if symptoms improve on their own.
- Call if you experience eye pain, redness, or sensitivity to light
- Seek care for any vision changes or blurriness
- Report discharge, tearing, or a feeling of something in your eye
- Get help if symptoms start after swimming, showering, or rinsing with water
If you experience severe pain, sudden vision loss, rapidly worsening symptoms, or cannot keep your eye open, seek emergency room or urgent ophthalmology care immediately.
Common Mistakes People Make with Tap Water and Contacts
Many contact lens wearers rinse their lens cases with tap water, thinking this keeps them clean. Unfortunately, this practice introduces bacteria and Acanthamoeba directly into your lens storage system. The organisms form biofilms inside the case that are very hard to remove.
Instead of tap water, we recommend rinsing your case with fresh contact lens solution. After rinsing, let the case air dry completely with the caps off. This simple change can dramatically reduce your risk of infection.
Running out of contact lens solution at night can be frustrating, but tap water is never an acceptable substitute. Some people use water just once and assume it will be fine, but even a single exposure can introduce dangerous organisms. Your eyes are too precious to take that risk.
- Remove your lenses and wear glasses until you get more solution
- If you must store lenses overnight, discard them and use a fresh pair the next day
- Keep a travel-size bottle of solution as a backup
- Consider switching to daily disposable lenses if you often forget supplies
Showering or swimming while wearing contact lenses is one of the most common ways people expose their eyes to tap water. The lenses act like sponges, soaking up water and trapping microorganisms against your cornea. Hot tubs and swimming pools are particularly risky because the warm water encourages organism growth.
We recommend removing your contacts before any water activity. If you need vision correction in the water, discuss prescription swim goggles with us. For showering, simply remove your lenses beforehand. If you must wear lenses in certain water situations, consider these harm-reduction steps:
- Use watertight swim goggles if swimming with lenses
- Consider daily disposable lenses for unavoidable water exposures and discard them immediately after
- Remove lenses immediately after any water exposure and complete a full disinfection cycle before re-wearing
- Never wear contact lenses in hot tubs under any circumstances
Adding tap water to contact lens solution to make it last longer destroys the solution's ability to disinfect your lenses. The chemicals in contact lens solution are carefully balanced to kill microorganisms, and diluting them makes them ineffective. Topping off old solution with water also introduces contaminants.
Always empty your case completely and fill it with fresh solution each time you store your lenses. Using the proper amount of solution costs pennies per day but protects your vision. We often tell patients that replacing solution is much cheaper than treating an eye infection.
Perhaps the most dangerous mistake is storing contact lenses in tap water, even for just one night. People do this when traveling or when they have forgotten their solution. During storage, your lenses absorb water and any organisms it contains, creating a concentrated dose of contamination.
- Lenses stored in water can become difficult or impossible to disinfect
- Water causes lenses to change shape and fit poorly
- Organisms multiply rapidly during overnight storage
- The risk of infection increases dramatically with each hour of exposure
How We Diagnose Tap Water-Related Eye Infections
When you come to our office with symptoms of a possible tap water exposure infection, we conduct a thorough examination right away. We will ask detailed questions about your contact lens habits, recent water exposure, and when your symptoms began. This history helps us determine which organisms might be causing your infection.
We use a special microscope called a slit lamp to examine your cornea under high magnification. Bright lights and filters let us see damage, inflammation, and signs of infection that are invisible to the naked eye. We may also use special dyes that highlight areas of corneal injury.
If we suspect a serious infection, we may perform a corneal scraping to collect a sample of cells and organisms from your eye. This procedure sounds scary but is done with numbing drops so you feel minimal discomfort. We gently remove a tiny amount of tissue from the affected area using a sterile instrument.
The sample goes to a laboratory where technicians culture it to identify the exact organism causing your infection. Culture results usually take several days, but they tell us which medications will work best. We often start treatment immediately and then adjust based on culture findings.
We may use advanced imaging to evaluate how deeply an infection has penetrated your cornea. Optical coherence tomography provides detailed cross-sectional images of corneal layers. Confocal microscopy can sometimes visualize Acanthamoeba cysts directly, which helps confirm this difficult diagnosis.
- Imaging shows the depth and extent of corneal involvement
- We can monitor how well treatment is working over time
- Pictures help us plan surgical intervention if needed
- Digital records document your condition for insurance and specialists
Time is critical when treating eye infections from tap water exposure. Bacterial infections can permanently damage your cornea within days if not treated promptly. Acanthamoeba infections are easier to control when caught early, before the organisms burrow deeply into tissue.
We urge you to contact us the same day you notice symptoms. Early diagnosis means we can start the right treatment immediately, which greatly improves your chances of a full recovery. Waiting even a few days can make the difference between clear vision and permanent damage.
Treatment Options and Recovery
Bacterial keratitis from tap water exposure requires intensive antibiotic eye drop treatment. We typically prescribe broad-spectrum antibiotic drops that you must use very frequently at first, sometimes every hour around the clock. The medication must be applied this often to maintain high levels in your corneal tissue.
As your infection improves, we will gradually reduce the frequency of drops. Most bacterial infections respond well to antibiotics within a few days, but you must complete the full course of treatment. Stopping too soon can allow the infection to rebound or fail to fully clear.
Acanthamoeba keratitis is much harder to treat than bacterial infections because few medications kill this organism effectively. We usually prescribe a combination of antiseptic drops that must be used around the clock for weeks or months. Two commonly used medications are polyhexamethylene biguanide and chlorhexidine, which may need to be specially compounded.
- Treatment often requires drops every hour for the first several days
- You may need multiple medications used in combination
- The treatment course typically lasts three to six months or longer
- We will see you frequently to monitor progress and adjust therapy
- Some cases require additional treatments if drops alone do not work
Eye infections from tap water can be extremely painful, making it hard to function normally. We may recommend oral pain medications to keep you comfortable during treatment. Wearing sunglasses, even indoors, can help with severe light sensitivity.
Cycloplegic eye drops relax the muscles inside your eye and can significantly reduce pain. These drops also keep your pupil dilated, which helps prevent complications. We monitor you closely when using these medications to ensure they are safe and effective for your situation.
If an infection causes severe scarring or does not respond to medication, we may recommend corneal transplant surgery. During this procedure, a surgeon removes the damaged portion of your cornea and replaces it with healthy donor tissue. This surgery can restore vision when other treatments have failed.
Corneal transplants are major operations that require careful evaluation and preparation. Recovery takes months, and you will need to use eye drops long-term to prevent rejection of the donor tissue. We coordinate closely with corneal specialists to ensure you receive the best possible care if surgery becomes necessary.
Treating tap water-related eye infections requires frequent follow-up appointments so we can track your progress. In the early stages, we may need to see you every day or every few days. At each visit, we examine your cornea to check if the infection is improving and adjust your treatment plan accordingly.
- Bring all your eye drops to every appointment
- We will check your vision and measure healing progress
- Tell us about any new symptoms or problems with your medications
- Follow-up care may continue for months after the infection clears
Protecting Your Eyes with Safe Contact Lens Habits
Not all contact lens solutions are the same, and using the right one is essential for preventing infections. We recommend multipurpose solutions that clean, disinfect, and store your lenses in one bottle. Make sure the solution you choose is approved for your specific type of contact lenses.
Never use homemade saline or solutions labeled only for rinsing. These products do not contain disinfectants and will not protect you from the organisms found in tap water. Check expiration dates regularly and throw away any solution that has been open for longer than the manufacturer recommends, which is often 60 to 90 days after opening per the label.
Hydrogen peroxide-based lens care systems are another effective option that may offer better disinfection for some lens types. These systems require a neutralization step before you can insert your lenses. Never put hydrogen peroxide solution directly in your eye, and always follow the manufacturer's neutralization instructions exactly. If you wear scleral lenses, use sterile preservative-free saline for filling the lens before insertion, not multipurpose solution and never tap water.
Proper lens care starts the moment you remove your contacts each night. Place one lens in the palm of your clean, dry hand and apply a few drops of fresh solution. Gently rub the lens in a back-and-forth motion for about 10 to 20 seconds per side, or as directed on the solution label, then rinse it with more solution.
- Wash your hands thoroughly with soap and dry them before touching lenses
- Rub and rinse each lens even if using a no-rub solution
- Fill your case with fresh solution, never reused or topped-off liquid
- Make sure lenses are fully submerged in solution in the closed case
- After inserting lenses in the morning, empty the case, rub and rinse it with fresh disinfecting solution (not water), wipe the inside with a clean tissue, and air dry it face down with caps off
- Let lenses soak for at least the minimum time recommended on the solution bottle
Your contact lens case harbors bacteria and other organisms even with regular cleaning. Biofilms develop on the inside surfaces and can contaminate your lenses no matter how much solution you use. We recommend replacing your lens case at least every three months.
Many solution manufacturers include a free case with each bottle, making replacement easy and affordable. Mark your calendar to remind yourself when to switch to a new case. If your case becomes cracked, discolored, or damaged in any way, replace it immediately regardless of how long you have used it.
Sleeping or napping while wearing contact lenses dramatically increases your risk of serious eye infections, even if you do everything else correctly. When your eyes are closed during sleep, less oxygen reaches your cornea and your natural tear flow decreases. These changes create conditions that help bacteria and other organisms thrive.
- Overnight lens wear increases infection risk by six to eight times compared to daily wear
- Even short naps in contact lenses raise your risk
- Remove your lenses before any planned or unplanned sleep
- Only sleep in lenses if you have been specifically fitted for extended-wear lenses and your eye doctor has approved continuous wear
- If you do wear approved extended-wear lenses, follow your prescribed replacement schedule exactly and attend all follow-up visits
Travel increases your risk of making mistakes with contact lens care, so careful planning is important. Pack more solution than you think you will need in case of delays or emergencies. Bring a backup pair of contact lenses and your glasses so you have vision options if problems occur.
Airport security allows contact lens solution in carry-on bags if bottles are 3.4 ounces or smaller, or you can purchase solution after passing through security. Never rely on being able to buy your preferred solution at your destination. If you do run short, use only sterile contact lens solution purchased from a pharmacy, never tap water.
Making it a firm rule to remove your contacts before water touches your face is the best way to prevent tap water exposure. This includes showering, bathing, swimming in pools or natural bodies of water, and using hot tubs. Even splashing water on your face while washing up poses some risk.
- Take out your lenses before getting in the shower or bath
- Never swim or snorkel while wearing contacts
- Remove lenses before water sports, even if wearing goggles
- Consider daily disposable lenses if your lifestyle involves frequent water exposure
Frequently Asked Questions
Distilled water and even sterile water are not safe for contact lenses. While sterile water is free of organisms when bottled, it lacks the disinfecting agents found in contact lens solution. Once opened, sterile water can become contaminated quickly. Distilled water also changes the shape of your lenses and can damage them, so always use only products specifically designed for contact lens care.
Remove your contact lenses immediately if tap water splashes in your eyes or touches your lenses. Follow these steps to protect your eyes:
- If daily disposables, discard them immediately
- If reusable soft lenses, strongly consider discarding them; if you must keep them, perform a complete rub-and-rinse cleaning and disinfection cycle per the solution label, and replace your lens case before storing
- Do not re-wear lenses until you are completely symptom-free; if any redness, pain, light sensitivity, discharge, or blurred vision occurs, seek same-day eye care
- Monitor your eyes for at least 2 to 4 weeks after exposure for delayed symptoms, especially severe pain or light sensitivity, as some infections develop slowly
- Bring the lenses, case, and solution bottle to your appointment if you develop symptoms
Saline solution alone is not safe for storing contact lenses because it does not contain disinfectants. You can use sterile saline to rinse lenses after cleaning them with multipurpose solution, but lenses must be stored in disinfecting solution. Some people confuse saline with multipurpose solution, so always read labels carefully. If a product says it is only for rinsing, you need a separate solution for storage and disinfection.
Symptoms of a tap water-related eye infection can appear within hours or may take several days to develop. Fast-growing bacteria like Pseudomonas can cause noticeable corneal damage within 24 hours of exposure. Acanthamoeba infections typically develop more slowly, with symptoms emerging over days or weeks. This variability is why we recommend being alert for any eye changes after water exposure and seeking help at the first sign of trouble.
Most health insurance plans and vision insurance policies cover medically necessary treatment for eye infections, including those caused by tap water exposure. Your coverage for medications, office visits, and procedures will depend on your specific plan benefits. We recommend contacting your insurance company when beginning treatment to understand your coverage and any out-of-pocket costs. Our office staff can help you navigate insurance questions and verify benefits.
Daily disposable contact lenses eliminate the risks associated with lens storage and cleaning because you throw them away after a single use. This makes them inherently safer when it comes to avoiding tap water contamination of your storage case and solution. However, you must still remove daily lenses before water activities and never rinse them with tap water if you need to reinsert them during the day. We may recommend daily disposable lenses if you have had infections in the past or struggle with proper lens care habits.
Getting Help for Why You Should Never Use Tap Water on Contact Lenses
Protecting your eyes from tap water exposure is one of the most important things you can do as a contact lens wearer. If you have questions about safe lens care or have experienced water exposure, our eye care team is here to help. We can review your lens care routine, recommend the best products for your needs, and provide emergency care if you develop symptoms of infection.