Contact lenses are designed to provide clear vision and comfort, so irritation signals that something is wrong. Discomfort often manifests as a scratchy, gritty sensation, persistent redness, or a burning feeling. Any change to the lens, the eye, or the environment can disrupt the balance of the tear film, leading to discomfort that should not be ignored.
Discomfort Caused by Lens Fit and Damage
A major source of irritation stems from the physical properties of the lens itself, particularly its dimensions and integrity. Contact lenses are prescribed with a specific base curve and diameter to match the unique shape of your cornea. If the lens is too flat or too steep, it will move improperly, causing discomfort. A lens that is too tight restricts the flow of tears and oxygen, while a lens that is too loose can cause excessive friction with every blink, leading to irritation and redness.
Lens damage is a direct cause of physical pain, introducing rough edges to the delicate surface of the eye. A tear, chip, or nick creates a jagged surface that can rub against the cornea or conjunctiva, causing a painful corneal abrasion. When lenses are worn past their recommended lifespan, they also accumulate protein and lipid deposits from the tear film, which roughens the surface and causes discomfort.
Issues Arising from Hygiene and Overwearing
Many instances of irritation relate directly to user habits, specifically improper cleaning and extended wear. Reusing or “topping off” old disinfecting solution, instead of using fresh solution, reduces the solution’s ability to kill microorganisms and leads to debris buildup. Not physically rubbing and rinsing the lenses, even with “no-rub” solutions, allows deposits to remain, which can trigger an inflammatory response.
Using tap water or saliva to clean or store lenses introduces a high risk of serious eye infections from microorganisms like Acanthamoeba. This organism, commonly found in water sources, can adhere to the lens and cause a severe corneal infection that is difficult to treat.
Wearing lenses for too many hours or sleeping in lenses not approved for overnight wear significantly reduces the oxygen supply to the cornea. Depriving the cornea of oxygen causes the eye to become red, swollen, and prone to infection. Exceeding the manufacturer’s replacement schedule, such as wearing a two-week lens for a month, also causes the lens material to degrade and accumulate excessive deposits, leading to chronic irritation.
Eye Health Conditions and Environmental Factors
Sometimes, discomfort is caused not by the lens itself, but by an underlying eye condition or external environmental stresses. Contact lens wear is a common cause of Dry Eye Syndrome, as the lens material absorbs moisture from the tear film, increasing the rate of evaporation. This results in a gritty, dry sensation that worsens throughout the day and is exacerbated by factors like staring at computer screens, which reduces the natural blink rate. Environmental irritants, such as smoke, dust, or low-humidity environments like air-conditioned offices, can also dry out the tear film rapidly, leading to discomfort.
Allergies are a frequent source of contact lens discomfort, as airborne particles like pollen or pet dander can stick to the lens surface. This traps the allergens against the eye, leading to intense itching, redness, and swelling. A condition known as Giant Papillary Conjunctivitis (GPC) can also develop, characterized by the formation of small, dome-shaped bumps on the inner surface of the upper eyelid. GPC is an inflammatory reaction to chronic friction or the buildup of protein deposits on the lens, making the eye feel intensely scratchy and intolerant to lens wear.
Immediate Remedies and Professional Consultation
When irritation first appears, the most immediate action is to remove the contact lenses and switch to glasses. This allows the cornea to receive full oxygenation and removes the source of friction or contamination. To alleviate dryness, use rewetting drops specifically formulated for contact lenses, avoiding over-the-counter drops that promise to “get the red out,” as these can cause rebound redness.
Seek professional consultation if you experience severe symptoms suggesting a serious problem. Severe, sudden eye pain, a noticeable drop in vision, extreme light sensitivity, or discharge are signs of a potential infection or corneal damage requiring immediate medical attention. Any persistent redness or discomfort lasting longer than 24 hours after removing the lenses should prompt a visit to an eye care professional. Only a comprehensive eye examination can accurately determine the cause of irritation and prescribe appropriate treatment.