Red Eye and Contact Lenses: Keratitis, Corneal Ulcers and When to Get Help
The key message for contact lens wearers
If your eye becomes red while you wear contact lenses, take the lenses out and arrange a same-day, in-person eye examination. Do not assume it is ordinary pink eye. Lens-related redness can be an early corneal infection (microbial keratitis), which can progress within a day or two and permanently damage vision.
Telehealth cannot rule this out. An optometrist or emergency department needs to examine the cornea with magnification and dye.
This page covers lens-specific risks. For general causes of red, sticky eyes, see our pink eye overview.
How common, and how serious?
In a 2020 UNSW Sydney overview of Australian research, bacterial eye infections were estimated to affect about 4 in every 10,000 contact lens wearers annually. The overview also reported substantial vision loss in around 13% of affected people. These are research estimates, not an individual risk prediction. Acanthamoeba keratitis, a rarer infection linked to water, is estimated to affect 10 to 20 Australian lens wearers each year, and some need a corneal transplant or more than a year of treatment.
The risk for any one wearer is low, but the consequences are severe enough that every lens-related red eye should be checked quickly.
What are microbial keratitis and corneal ulcers?
The cornea is the clear window at the front of the eye. Keratitis means the cornea is inflamed; microbial keratitis means it is infected. A corneal ulcer is an area where the corneal surface has broken down, often because of infection. On examination it may show as a white or grey spot.
Organisms that cause lens-related infection
- Bacteria cause most cases. Pseudomonas aeruginosa is particularly important in lens wearers and can progress quickly.
- Fungi, such as Fusarium, are less common. They are more likely in warm, humid climates, including northern Australia, and after an eye injury from plant material.
- Acanthamoeba is an amoeba found in tap water, pools, spas, the sea and soil. It is rare, but very painful and hard to treat.
Why lenses raise the risk
Lenses reduce the oxygen and tear flow reaching the cornea, can cause tiny surface scratches, and can hold organisms against the eye. Lens cases can develop a biofilm, a sticky layer where microbes survive disinfecting solutions. Sleeping in lenses magnifies all of these effects.
Risk factors you can change
| Risk factor | Why it matters | What to do |
|---|---|---|
| Sleeping or napping in lenses | The biggest single risk factor in Australian research, whatever the lens material | Remove lenses before any sleep, unless your optometrist has prescribed overnight wear |
| Water contact | Tap water, showers, pools, spas and the sea can carry Acanthamoeba | Keep lenses and cases away from all water; never rinse them under the tap |
| Poor case hygiene | Old or dirty cases grow biofilm that disinfecting solution cannot clear | Rinse with fresh solution, air-dry face down, replace regularly |
| Topping up old solution | Weakens disinfection | Empty the case and use fresh solution every time |
| Over-wearing lenses | Lenses worn beyond their schedule collect deposits and damage | Follow the replacement schedule for your lens type |
| Smoking | Linked to higher infection rates in lens wearers | Another reason to quit; ask your GP about support |
| Buying lenses online without regular reviews | Linked to higher risk, probably because fit and hygiene are checked less often | Keep regular optometrist check-ups |
| Decorative or costume lenses | Often worn without a professional fitting or care instructions | Only wear lenses fitted by an optometrist |
Symptoms that should never be managed as routine pink eye
- eye pain, especially pain that seems out of proportion to how red the eye looks
- sensitivity to light, or difficulty keeping the eye open
- blurred, reduced or fluctuating vision
- a white, grey or cloudy spot on the cornea
- increasing watering, discharge, swelling, or a feeling that something is stuck in the eye after the lens is out
- redness after sleeping in lenses, or after swimming or showering in them
Any red eye in a contact lens wearer warrants a same-day assessment, even without these symptoms. Go to an emergency department for severe pain, sudden loss of vision, or worsening symptoms when you cannot see an optometrist the same day.
Acanthamoeba keratitis can be deceptive: pain is often severe, symptoms may improve and then return, and it can be mistaken for other eye infections. Tell the clinician if your lenses have been in contact with water.
Not every lens-related red eye is an infection, but only an examination can tell
Several lens problems look similar at first. The table shows typical patterns. They overlap, which is why the same-day check still applies.
| Condition | Typical features | How soon to be seen |
|---|---|---|
| Microbial keratitis or corneal ulcer | Pain, light sensitivity, blurred vision, discharge, white spot on the cornea | Same day; emergency if severe |
| Acanthamoeba keratitis | Severe pain, slow onset, history of water contact; may come and go | Same day; usually managed by an eye specialist |
| Contact lens peripheral ulcer | Small white spot near the edge of the cornea with moderate discomfort; often inflammatory rather than infected | Same day, because it cannot be told apart from infection without an examination |
| Contact lens acute red eye | Waking with a red, painful eye after sleeping in lenses | Same day |
| Giant papillary conjunctivitis | Itch, stringy mucus, lenses moving or blurring, bumps under the upper eyelid; develops over weeks | Optometrist within days; stop lens wear |
| Solution sensitivity, over-wear or dry eye | Mild irritation in both eyes, often worse later in the day | Remove lenses; arrange a same-day assessment for any new red eye while wearing lenses |
| Conjunctivitis | Redness with watery or sticky discharge, often with a cold or hay fever | Same day while lenses are involved, to rule out keratitis |
What to do right now
- Remove both lenses. Wash and dry your hands first. Do not put the lenses back in, even if the eye feels better.
- Keep the evidence. Put the lenses, case and solution bottle in a clean bag and take them to your appointment. The clinician may want to test them.
- Switch to glasses. Do not cover the eye with a patch, which can encourage some bacteria to grow.
- Book a same-day examination. Optometrists can see you without a referral, and many have equipment to examine the cornea and can refer you directly to an eye specialist. Major cities have dedicated eye emergency departments, such as the Royal Victorian Eye and Ear Hospital in Melbourne and Sydney Eye Hospital. After hours, go to your nearest emergency department.
- Avoid self-treatment. Do not use leftover antibiotic or steroid drops, redness-relief drops, or lens solution as eye drops.
- Do not drive if your vision is affected.
What happens at the eye examination
- Your vision is measured in each eye.
- The cornea is examined under a slit lamp microscope, usually after a drop of fluorescein dye, which highlights scratches and ulcers.
- If an ulcer is found, the clinician may gently scrape the surface to identify the organism.
- Treatment for keratitis often involves frequent antibiotic drops, sometimes every hour at first, including overnight, with close follow-up over the next few days.
- Steroid drops are sometimes added later by an eye specialist, but should never be started without one.
- Acanthamoeba and fungal infections need specialist treatment that can last for months.
Why telehealth is not the right first stop
A phone or video consultation cannot reliably rule out a corneal ulcer or microbial keratitis, because it cannot measure your vision accurately or show the cornea under magnification. For a contact lens wearer with a red eye, a same-day in-person examination comes first, rather than a routine online pink eye consultation.
Telehealth can still help with lower-risk eye concerns, such as itchy allergic eyes when you are not wearing lenses, or questions after your optometrist has examined you.
Getting back into lenses safely
- Wait until your optometrist or eye specialist confirms the eye has healed.
- Healthdirect advises wearing glasses for at least a week after symptoms have gone.
- Throw away disposable lenses and the case used before or during the infection. Ask your optometrist whether other lenses can be disinfected or need replacing.
- Ask whether a different lens type, such as daily disposables, or a change in wearing schedule would lower your risk.
A safer daily lens routine
- Clean hands. Wash with soap and water and dry thoroughly before touching your lenses.
- Rub and rinse. If your lenses are reusable, rub and rinse them with fresh disinfecting solution as directed, even if the product says no rub.
- Fresh solution every time. Empty the case completely; never top up old solution.
- Care for the case. Rinse it with fresh solution, not tap water, leave it to air-dry face down, and replace it regularly. Many optometrists recommend every one to three months.
- Use peroxide systems exactly as directed. Use only the supplied case and wait the full neutralising time. Unneutralised hydrogen peroxide burns the eye.
- Remove before sleep. This includes naps, unless your lenses are prescribed for overnight wear and you are under regular review.
- No water. Take lenses out before showering, swimming or using a spa. If you must swim in lenses, use tight goggles and daily disposables, and throw the lenses away afterwards. Never use saliva or homemade saline.
- Keep a backup. Keep an up-to-date pair of glasses so you can stop lens wear the moment your eye is uncomfortable.
Daily disposables avoid storage-case risks, but they do not remove the risk of infection, especially if you sleep in them or expose them to water.
Children and teenagers who wear lenses
Orthokeratology (ortho-k) lenses are worn overnight to slow or correct short-sightedness, so the precautions for overnight wear apply. Supervise lens care, keep tap water away from lenses and cases, and treat any red or painful eye as a same-day optometrist visit. Teenagers are more likely to sleep in lenses, swim in them or wear decorative lenses, so it helps to go over the rules with them. For other age-specific advice, see pink eye in children and adults.
Common questions
Can I wear contact lenses if I have pink eye?
No. Stop wearing lenses until an eye-care professional has examined you and the eye has fully recovered. Healthdirect suggests glasses for at least a week after symptoms have gone.
Can I use redness-relief drops and wait until tomorrow?
No. Do not delay assessment of lens-related redness. Redness-relief drops can hide symptoms without treating a corneal infection.
Is a red eye after sleeping in my lenses an emergency?
It needs a same-day examination. Sleeping in lenses is the strongest risk factor for corneal infection. Go to an emergency department if the pain is severe or your vision is affected.
Are daily disposable lenses safer?
They remove the risks of storage cases and solutions, but infections still occur, particularly with overnight wear or water contact. Use each pair once.
Can I swim with contact lenses?
It is best not to, because water can carry Acanthamoeba. The safest option is to remove contact lenses before swimming; goggles do not eliminate infection risk.
Can I reuse my lenses after treatment?
Ask your eye-care professional. Lenses and cases that may be contaminated commonly need replacing.
Can a telehealth doctor diagnose keratitis?
No. Diagnosing keratitis requires an in-person examination with magnification and dye.
Sources and further reading
This article is general information and does not replace an individual eye examination or medical advice.
- Healthdirect Australia: Conjunctivitis
- UNSW Sydney (Dr Nicole Carnt): How to keep your contact lenses clean, and what can go wrong
- Optometry Australia: Why you should not wear contact lenses in the shower
- American Academy of Ophthalmology: Overnight contact lens wear remains major risk factor (summary of Australian research)
Need guidance about eye symptoms?
If you wear contact lenses and your eye is red or painful, take your lenses out and see an optometrist or emergency department today.
For other mild eye symptoms without warning signs, such as itchy allergic eyes while you are not wearing lenses, a DocTel GP can advise by video. In an emergency, call 000.