6 min




Getting in from a night out, going for a quick swim before work – it can be tempting to leave in your contacts. But it’s important to know that poor contact lens habits and hygiene can cause serious problems. For instance, you’re four times more likely to get eye infections if you sleep in your contacts.

Serious infections are pretty rare, but once they develop, they can be hard to treat – and in some cases, can cause blindness. There are several ways that contact lenses can cause infections if they’re not used properly.

Check Your Eye Health - 60-Second Eye Test

“Contact lenses rub against your cornea, creating microabrasions - opening ‘little doorways’ for bacteria to get in, increasing the risk of infection.”


  • Sleeping in contact lenses increases your chance of getting a corneal infection (the cornea is the clear film that covers the coloured part of your eye). This is because your cornea doesn’t have its own blood vessels and relies on air in the atmosphere for oxygen. Contact lenses act as a sort of mask in this respect – they make it harder for oxygen to permeate; especially during sleep, when your eyes are closed. Over time, this can cause little ulcers to form on the front part of the eye, which increases the risk of infections. Taking out your contact lenses before you sleep helps your cornea to replenish the oxygen deficit and reduce the risk of infections.

  • Swimming pools, lakes, rivers, and the ocean contain microscopic bacteria called Acanthamoeba (chlorine in swimming pools doesn’t kill all pathogens). Contact lenses are highly absorbent, so when you swim in them, any Acanthamoeba present can end up getting trapped between the contact lenses and your eyes. Contact lenses make little cuts (microabrasions) on the surface of your eyes, which can act as ‘little doorways’ for this bacteria to get in. This, in turn, can cause an infection known as Acanthamoeba Keratitis.

  • If you can, it’s best to use daily disposable contact lenses rather than reusable ones. This is because there’s less time for them to get contaminated with protein and deposits of atmospheric dirt. Biofilm is a slimy coating that your body creates when a foreign object is present (like a contact lens) – and this, unfortunately, attracts bacteria. Changing your contacts daily means there isn’t enough time for biofilm to build up and cause an infection. If you’re not able to use daily disposables because of your prescription or some other condition, make sure you always soak them in fresh solution overnight – but never in tap water!

  • Swapping your contacts for glasses at least one day a week gives your cornea a chance to recover and ‘breathe’. This also lets your tear film stabilise, reducing the risk of dry eyes and infections.

  • Many eye drops and sprays contain preservatives, which can, over time, cause allergies and sensitivity – including irritation to the cornea. As a contact lens wearer, you should always use preservative-free eye drops and sprays that moisturise your eyes without creating other long-term issues.

  • Good quality eye vitamins can help with Dry Eyes and long-term eye health. The main ingredients to look out for are vitamins A, D, C and E, and Lutein and Zeaxanthin, while B2, B6, B9, B12 and zinc are also recognised as promoting good vision and maintaining eye health. Omega-3 fatty acids and maqui berry can also be taken to maintain the health of the lubricating glands in your eyes, which keep your eyes well moisturised.

  • Contact lenses are highly absorbent, so it’s important to always wash and dry your hands before touching them. Drying is particularly important because water carries all types of bacteria and microbes that can cause infections.

  • If you use daily disposable lenses, you should always use a fresh set every day – and never, ever reuse them. Reusing daily disposable contact lenses is one of the most common causes of corneal infections. Alex describes how leaving them in for too long creates a ‘harbour in a storm’ for bacteria – a safe place for them to accumulate and grow. Some types of corneal infections, if left untreated or not managed promptly, may lead to blindness.

  • MICROABRASIONS & biofilm explained

    Contact lenses can cause tiny little cuts on the surface of your eye. These microabrasions form every time you blink – as your contact lenses rub against and scratch your cornea.

    When your body comes into contact with a foreign object – like contact lenses – your body’s natural defence mechanism coats them in a biofilm. This is a slimy protective layer which attracts bacteria. Changing your contact lenses frequently stops them from becoming a breeding ground for bacteria.

    Your Complete Guide To Dry Eyes

    “Infections can cause your cornea to scar and turn cloudy. Once this happens, it’s almost impossible to reverse.”

    let your eyes 'breathe'

    Your cornea doesn’t have its own blood supply like other body parts. They absorb oxygen directly from the air. Because they don’t have blood vessels, they can remain transparent.

    Contact lenses sit in front of the cornea, preventing oxygen from floating in and disturbing your tear film. This reduces the oxygen getting to the cornea and can increase the likelihood of corneal infections. Luckily, today’s silicone contact lenses are much better at letting oxygen through your cornea than older products.

    Eye Drops + Eye Spray


    If you’ve been wearing contact lenses for a long time (say, 10 years or more), you may build up an intolerance to them. If that’s the case, you’ll develop a strong allergic reaction – which will persist even if you change the brand of contact lenses (as they’re essentially made of the same materials).

    If this happens, you should stop using contact lenses and move back to wearing glasses. Corrective laser eye surgery may also be an option for you.

    Complete Guide to Laser Eye Surgery

    Is it safe to wear contact lenses while flying?

    Although wearing contact lenses while flying is generally safe, some factors can lead to increased risks of dry eyes, irritation, and eye infections:

    • Low humidity: Airplane cabins have low humidity levels, typically 10-20%, significantly lower than the recommended 30-50% indoor humidity. Low humidity can cause the tear film, which provides moisture and lubrication to the eyes, to evaporate more rapidly. This can result in dry and irritated eyes.
    • Decreased air pressure: inside an aeroplane cabin is lower than at sea level. This decreased air pressure can reduce oxygen supply to the cornea, causing discomfort and potentially impacting lens fit, especially for long flights or those who wear contact lenses for extended periods.
    • Airborne irritants: such as dust or allergens, can become trapped between the contact lens and the eye, causing irritation or even an allergic reaction.

    Is it safe to wear contact lenses while flying? (Cont.)

    To minimise the risks with wearing contact lenses while flying:

    • Use daily disposable lenses: Daily disposable contact lenses can reduce the risk of irritation and infections.
    • Use preservative-free eye drops & sprays: to help maintain eye moisture during the flight.
    • Remove lenses during sleep: If you plan to sleep during the flight, remove your contact lenses.
    • Wear glasses during the flight: and switch to contact lenses upon arrival at your destination. This will give your eyes a break and allow them to rehydrate and adjust to the cabin environment.
    • Maintain proper lens hygiene: Ensure your contact lenses and lens case are clean and disinfected before the flight. Wash your hands thoroughly before handling your lenses, and avoid touching your eyes or lenses unnecessarily during the flight.
    • Stay hydrated: Drinking water regularly during the flight can help maintain overall body hydration, which also benefits eye health.


    1. Wash and dry your hands.
    2. Open the pouch (daily disposables) or case (reusable lenses) and scoop the lens out with your index finger.
    3. Check the lens. It should be a bowl shape. If it is inverted or has a ‘lip’, it’s inside out. Before putting it on, hold it up to check for any rips, scratches or dirt.
    4. If it’s dirty, use some fresh solution to clean it. But if it’s damaged, you should throw it away.
    5. Place the lens on the tip of your index finger, and pull the top eyelid up with your free hand – this will help stop you from blinking while putting them on.
    6. Pull down your bottom eyelid to centre the lens on your eye.
    7. You shouldn’t have to press it onto your eye – it should go into place on its own.
    8. Once the lens is on, blink and move your eyes from side to side several times. This helps remove any air bubbles trapped under the lens.
    9. Repeat for the other eye.


    Without touching your eyes

    1. Always wash and dry your hands.
    2. Facing a mirror, tilt your head slightly and pull down your lower eyelid.
    3. With your index finger, move the lens down onto the white of your eye and then with your thumb, gently pinch it out.
    4. Repeat for the other eye.
    Makeup & Eye Health


    How to avoid eye infections

    1. After removing your lenses, with a few drops of the cleaning solution, rub them gently for about 20 seconds.
    2. Place them carefully in your contact lens case to safely store your lenses. Your contact lens case should be clean and filled with fresh solution.
    3. Always read the instructions on the cleaning solution to make sure you’re cleaning and storing the lenses in the right way.
    4. Never use tap water to clean your lenses or contact lens case, as this can lead to eye infections.


    Sometimes, a soft contact lens folds in half and gets stuck under your upper eyelid. Don’t worry - the lens won’t get trapped behind or lost in your eye. Most of the time, the folded lens will move back to where you can see and remove it.

    However, if you can’t find your “lost” lens, try gently turning your upper eyelid inside out. The best way to do this is to place a cotton bud over one eyelid. Then hold the eyelashes on the lid and gently pull the eyelid down - flipping it inside out by folding it over the cotton bud. You should be able to see the folded lens. Gently move the contact lens with your inverted eyelid until it moves to where you can remove it.

    If you’re still struggling to remove the lens - ask someone to help or see your optician.


    See More
    Banish Eye Bags for Good
    5 min

    Banish Eye Bags for Good

    Makeup & Eye Health - The Ultimate Guide
    5 min

    Makeup & Eye Health - The Ultimate Guide

    Dry Eyes - Your Complete Guide
    6 min

    Dry Eyes - Your Complete Guide

    MTHK Eye Drops + Eye Spray - Preservative-free with Liposomes and 0.3% Hyaluronic Acid
    1036 reviews

    Complete Guide To Contact lenses - Resources & References

    1. Stapleton, F., Keay, L., Edwards, K., & Naduvilath, T. (2013). The epidemiology of contact lens related infiltrates. Optometry and Vision Science, 90(4), 313-324.
    2. https://journals.lww.com/optvissci/Abstract/2013/04000/The_Epidemiology_of_Contact_Lens_Related.2.aspx
    3. Dart, J. K. G. (1998). Predisposing factors in microbial keratitis: The significance of contact lens wear. British Journal of Ophthalmology, 82(7), 776-779.
    4. Acanthamoeba Keratitis: Centers for Disease Control and Prevention. (2019, May 1). https://www.cdc.gov/parasites/acanthamoeba/index.html
    5. Seal, D. V., Kirkness, C. M., & Bennett, H. G. B. (1999). Acanthamoeba keratitis in Scotland: Risk factors for contact lens wearers. Contact Lens and Anterior Eye, 22(2), 58-68.
    6. Dumbleton, K. A., Chalmers, R. L., Richter, D. B., & Fonn, D. (2013). Vascular response to extended wear of hydrogel lenses with high and low oxygen permeability. Optometry and Vision Science, 90(3), 215-223.
    7. https://journals.lww.com/optvissci/Abstract/2013/03000/Vascular_Response_to_Extended_Wear_of_Hydrogel.2.aspx
    8. Weikel, K. A., Garber, C., & Babino, D. (2014). Nutritional modulation of cataract. Nutrition Reviews, 72(1), 30-47.
    9. Reynolds, R. D. (1996). Vitamin B6, vitamin C, and carpal tunnel syndrome. Journal of the American College of Nutrition, 15(5), 493-496. https://www.tandfonline.com/doi/abs/10.1080/07315724.1996.10718621
    10. Pinazo-Duran, M. D., Gallego-Pinazo, R., Garcia-Medina, J. J., Zanon-Moreno, V., Nucci, C., Dolz-Marco, R., & Martinez-Castillo, S. (2013). Oxidative stress and its downstream signaling in aging eyes. Clinical Interventions in Aging, 8, 637-652. https://www.dovepress.com/oxidative-stress-and-its-downstream-signaling-in-aging-eyes-peer-reviewed-article-CIA
    11. Skorin, L., & Knutson, S. (2019). The role of omega-3 and omega-6 essential fatty acids in eye care. EyeNet Magazine. https://www.aao.org/eyenet/article/role-of-omega-3-omega-6-essential-fatty-acids-in-e
    12. Boscia, F., La Tegola, M. G., & Alessio, G. (2018). The role of topical MaquiBright in dry eye. European Review for Medical and Pharmacological Sciences, 22(21), 7127-7133. https://www.europeanreview.org/article/17087
    13. Szczotka-Flynn, L. B., Pearlman, E., & Ghannoum, M. (2010). Microbial contamination of contact lenses, lens care solutions, and their accessories: a literature review. Eye & Contact Lens: Science & Clinical Practice, 36(2), 116-129.
    14. Nixon, G. J., Louis, D., Speedwell, L., & Rimmer, S. (1999). An investigation into the viability of silicone elastomer contact lenses as a potential ocular drug delivery system. Contact Lens and Anterior Eye, 22(2), 69-75.
    15. Donshik, P. C., Ehlers, W. H., & Anderson, L. D. (1999). Strategies to better engage, educate, and empower patient compliance and safe lens wear: Compliance: What We Know, What We Do Not Know, and What We Need to Know. Eye & Contact Lens: Science & Clinical Practice, 25(4), 217-221.
    16. Bilkhu, P. S., Naroo, S. A., & Wolffsohn, J. S. (2014). Effect of a commercially available warm compress on eyelid temperature and tear film in healthy eyes. Optometry and Vision Science, 91(2), 163-170. https://journals.lww.com/optvissci/Abstract/2014/02000/Effect_of_a_Commercially_Available_Warm_Compress.8.aspx