Contact Lens Infection Symptoms: How to Tell If Your Eye Is Infected

Contact lenses are safe and effective vision-correction tools when used correctly, but improper hygiene, overuse, or ignoring early warning signs can quickly lead to serious eye infections. Many people search for contact lens infection symptoms because the initial signs are often subtle and easily mistaken for dry eyes or mild irritation. Unfortunately, delaying treatment can increase the risk of complications, including corneal damage or vision loss. 

This article explains how to recognise a contact lens eye infection, what causes it, how to tell infection apart from irritation or allergy, and when you should immediately stop wearing lenses and seek professional care.

What is a contact lens eye infection?

A contact lens eye infection occurs when harmful microorganisms enter and multiply in the eye, often due to contaminated lenses or poor hygiene practices. These infections can affect the cornea, conjunctiva, or surrounding tissues, depending on severity and cause.

Without prompt treatment, a contact lens infection can progress rapidly, making early recognition essential.

Common Contact Lens Infection Symptoms

Recognising contact lens infection symptoms early can significantly reduce the risk of long-term eye damage. Symptoms often worsen if contact lens use continues.

Early Symptoms

In the initial stage, contact lens infection symptoms may appear mild and intermittent, making them easy to dismiss.

Early warning signs include:

• Persistent redness - Eye redness that doesn't improve after removing lenses

• Unusual discomfort - Itching or irritation different from normal dryness

• Excessive tearing - Watery eyes beyond typical environmental response

• Mild light sensitivity - Slight discomfort in bright light

These early contact lens infection symptoms are often mistaken for tiredness or allergies, allowing infection to progress. Never ignore persistent discomfort—removing lenses immediately and monitoring symptoms prevents worsening.

Moderate to Severe Symptoms

As infection advances, contact lens infection symptoms become more noticeable and painful, indicating serious corneal involvement.

Advanced warning signs include:

• Sharp or burning pain - Intense eye pain worsening with movement

• Thick discharge - Yellow, green, or white discharge indicating bacterial or fungal infection

• Vision changes - Blurred or reduced vision that doesn't clear

• Eyelid swelling - Puffy, inflamed eyelids or surrounding tissue

• Severe photophobia - Extreme light sensitivity making it difficult to keep eyes open

At this stage of contact lens infection symptoms, immediate medical attention is essential. Discontinue lens wear completely and contact your eye care professional urgently. Delayed treatment can result in corneal ulcers, scarring, and permanent vision loss.

What Causes Contact Lens Infections?

Contact lens infections occur when harmful microorganisms bacteria, fungi, viruses, or parasites invade the eye's surface, leading to potentially serious contact lens infection symptoms. Understanding these causes helps prevent infections before they develop.

Bacterial Infections

Bacteria are the most common cause of contact lens infections, with certain species posing particular risks to lens wearers.

Common bacterial culprits:

• Pseudomonas aeruginosa - Thrives in moist environments, rapidly causes severe corneal damage and contact lens infection symptoms

• Staphylococcus aureus - Lives on skin and eyelids, transfers to lenses through poor hand hygiene

• Serratia marcescens - Found in contaminated lens cases and tap water exposure

Bacterial contact lens infections typically develop from contaminated storage cases, improper cleaning routines, or wearing lenses while swimming. These infections progress quickly, causing severe contact lens infection symptoms within 24-48 hours including pain, discharge, and vision changes.

>>> See more: Mastering Contact Lenses: Wear & Care Guide

Fungal Infections

Fungal contact lens infections are less common but more difficult to treat, often requiring prolonged antifungal therapy and causing serious complications.

Fungal infection sources:

• Fusarium and Aspergillus species - Contaminate lens cases through environmental exposure

• Plant matter contact - Working in gardens or agricultural settings increases fungal exposure risk

• Homemade saline solutions - Using non-sterile water creates fungal contamination

Fungal contact lens infection symptoms develop more slowly than bacterial infections but are equally dangerous, causing progressive corneal infiltration and potential vision loss if untreated.

Acanthamoeba Infections

Acanthamoeba keratitis represents one of the most severe contact lens infections, caused by microscopic parasites found in water sources worldwide.

Acanthamoeba exposure sources:

• Tap water contact - Rinsing lenses or cases with tap water introduces parasites

• Swimming or showering in lenses - Water exposure while wearing contacts allows parasite attachment

• Contaminated lens solutions - Improperly stored or expired solutions harbor Acanthamoeba

Acanthamoeba contact lens infection symptoms are particularly painful and difficult to treat, often requiring months of intensive therapy. This infection causes characteristic severe eye pain disproportionate to clinical findings, along with ring-shaped corneal infiltrate visible on examination.

Poor Hygiene and Contamination

The majority of contact lens infections stem from preventable hygiene failures rather than unavoidable exposure.

Primary contamination sources:

• Contaminated lens cases - Cases not cleaned, dried, or replaced regularly become bacterial breeding grounds

• Dirty hands - Handling lenses without thorough handwashing transfers microorganisms directly to eyes

• Improper solution use - Topping off old solution, using expired products, or mixing solution types

• Extended wear violations - Sleeping in lenses not approved for overnight wear or wearing beyond replacement schedules

>>> See more: How To Care Your Contact Lens For Eye Health and Lens Longevity

Risk Factors That Increase Infection Likelihood

Certain behaviors and conditions significantly elevate your risk of developing contact lens infection symptoms.

High-risk practices:

• Sleeping in contact lenses increases infection risk 6-8 times

• Swimming, showering, or hot tubbing while wearing lenses

• Not replacing lenses according to prescribed schedules

• Reusing contact lens solution or storing lenses in water

• Smoking, which compromises eye surface immunity

How to Tell If It’s an Infection or Just Irritation

Distinguishing between minor irritation and genuine contact lens infection symptoms can be challenging, but understanding key differences helps you respond appropriately and seek timely care.

If you're uncertain whether you're experiencing irritation or contact lens infection symptoms, err on the side of caution. Seek immediate professional evaluation if discomfort persists beyond 2-3 hours after lens removal, if pain intensifies rather than improves, if any discharge appears, or if vision doesn't return to normal.

Early treatment of contact lens infection symptoms prevents serious complications including corneal ulcers, scarring, and permanent vision damage. Never adopt a "wait and see" approach when contact lens infection symptoms are suspected prompt medical intervention is essential for protecting your sight.

>>> See more: Can you be allergic to contact lenses? The helpful tips for you

What to Do If You Notice Contact Lens Infection Symptoms

Recognizing contact lens infection symptoms and responding immediately can prevent serious complications and preserve your vision. Quick, appropriate action is critical when contact lens infection is suspected.

Immediate Actions to Take: When you first notice potential contact lens infection symptoms, take these urgent steps to protect your eyes.

Remove Lenses Immediately: Stop wearing your contact lenses the moment you suspect contact lens infection. Continuing to wear lenses traps bacteria against your cornea, allowing the contact lens infection to worsen rapidly. Remove both lenses even if symptoms appear in only one eye.

Do Not Rub Your Eyes: Avoid rubbing or touching the affected eye, as this can spread contact lens infection, damage the corneal surface, or introduce additional contaminants. Rubbing worsens contact lens infection symptoms by causing mechanical trauma to inflamed tissue.

Discard Current Lenses and Case: Throw away the lenses you were wearing when contact lens infection symptoms appeared, never attempt to clean and reuse them. Discard your lens case, as it's likely contaminated with the same microorganisms causing your contact lens infection.

Switch to Glasses: Wear prescription glasses exclusively until your eye care professional clears you to resume contact lens wear. Even if contact lens infection symptoms improve, premature lens use can trigger recurrence.

>>> See more: How Often Should You Replace Your Contact Lenses?

Contact your eye care professional immediately upon noticing contact lens infection symptoms. Seek emergency care if you experience severe worsening pain, significant vision loss, symptoms outside office hours, or cannot reach your provider. Contact lens infection can cause permanent vision damage within 24-48 hours—prompt treatment is essential for protecting your sight.