Sore eyes are most commonly caused by digital eye strain, dry eye, allergies, or an infection like conjunctivitis. Less often, the soreness signals something more serious, such as corneal damage or internal inflammation. The cause usually determines whether the soreness resolves on its own or needs treatment, so understanding the differences matters.
Digital Eye Strain
Spending long hours on screens is one of the most common reasons eyes feel sore, achy, or tired. Roughly two-thirds of adults aged 30 to 49 spend five or more hours a day on digital devices, and that level of use is enough to produce noticeable symptoms in about half of people. Contact lens wearers are even more susceptible: with six or more hours of screen time, about 65% experience symptoms compared to 50% of non-wearers.
The soreness happens through two separate mechanisms. First, your eyes have to constantly refocus to keep a screen sharp at close range, which fatigues the tiny muscles inside each eye. That produces a deep ache or strain behind the eyes. Second, you blink less often and less completely while staring at a screen. Incomplete blinks leave parts of the cornea exposed, and the tear film dries out faster than it can replenish. That triggers burning, irritation, and a gritty feeling on the surface.
Taking regular breaks (looking at something 20 feet away for 20 seconds every 20 minutes) helps both problems. Consciously blinking more fully and using preservative-free artificial tears can address the dryness side specifically.
Dry Eye Disease
Dry eye goes beyond occasional screen-related dryness. It’s a chronic condition where the tear film breaks down too quickly or isn’t produced in sufficient quantity. Depending on how it’s measured, dry eye affects anywhere from 5% to 50% of adults, making it extremely common. The soreness tends to be a persistent burning or stinging, often worse in air-conditioned rooms, windy environments, or toward the end of the day.
Over-the-counter artificial tears with lubricating ingredients (called demulcents) reduce friction on the eye surface and are the first line of relief. Emollient-based drops help if the skin around your eyes is cracked or irritated. Omega-3 fatty acid supplements have also shown benefit in clinical trials for people who use screens more than three hours daily. If artificial tears aren’t enough, prescription anti-inflammatory drops may be needed.
Allergies
Allergic conjunctivitis is the most common allergic eye condition. When pollen, dust mites, pet dander, or mold reach your eye surface, immune cells in the conjunctiva (the thin membrane covering the white of your eye) release histamine and other inflammatory chemicals. That cascade causes itching, redness, watery eyes, and soreness that can range from mild irritation to a heavy, swollen feeling around the lids.
The itching is the key distinguishing feature. Infections and dry eye rarely itch the way allergies do. Over-the-counter antihistamine eye drops or oral antihistamines usually control symptoms. Avoiding the trigger, when possible, prevents the cycle from restarting.
Infections: Viral and Bacterial Conjunctivitis
Pink eye is the classic infectious cause of sore eyes, and most cases in adults are viral. Viral conjunctivitis typically produces a watery discharge during the day and sticky, crusted lids in the morning. Bacterial conjunctivitis causes a thicker yellow or green discharge that persists throughout the day. Both types make eyes red, sore, and sensitive to light.
Viral conjunctivitis has no specific treatment and clears on its own in one to two weeks. Bacterial conjunctivitis also resolves without treatment, but antibiotic drops can shorten the course to about five to seven days. Both forms are contagious. The CDC advises staying home from work or school if you can’t avoid close contact with others, and returning once symptoms improve or a clinician gives approval.
Contact Lens Overuse
Wearing contact lenses longer than recommended starves the cornea of oxygen. The corneal surface is covered by a thin layer of cells that depends on oxygen from the air (since there are no blood vessels supplying it directly). When a lens blocks that supply for too long, these cells start to break down, creating what amounts to an open sore on the cornea.
Early signs include redness, a gritty or burning sensation, and bloodshot eyes from new blood vessels growing on the white of the eye as the body tries to deliver oxygen another way. If caught early, stopping lens wear for a period lets the cornea heal. Left too long, the abrasion can become infected and cause scarring or permanent vision changes. Severe cases may require prescription antibiotic and steroid drops, and you may not be able to wear lenses again for weeks or longer.
Corneal Inflammation (Keratitis)
Keratitis is inflammation of the cornea itself, and it causes a deeper, more intense pain than surface-level irritation. It can be triggered by bacteria (commonly staphylococcus or pseudomonas), viruses like herpes simplex, fungi, or parasites. Swimming in oceans, rivers, lakes, or hot tubs is a well-known risk factor, as microorganisms in the water can enter the eye. Contact lens wearers who swim without removing their lenses or who clean lenses with tap water are at higher risk.
Non-infectious keratitis can also develop from a minor scratch, a foreign body in the eye, or wearing contacts too long. A previous corneal injury makes the eye more vulnerable to future episodes. Keratitis needs professional evaluation because untreated infections can progress to corneal ulcers and permanent vision loss.
Internal Eye Inflammation (Uveitis)
When the soreness feels deep inside the eye, accompanied by light sensitivity, blurred vision, or floaters, the cause may be uveitis. This is inflammation of the middle layer of the eye, and it can happen for unknown reasons or as a complication of autoimmune conditions. Inflammatory bowel disease, lupus, sarcoidosis, and Behçet’s disease are all linked to uveitis. A specific genetic marker called HLA-B27, found in people with certain types of inflammatory arthritis (including ankylosing spondylitis and psoriatic arthritis), also increases the risk.
Uveitis can also result from infections, including toxoplasmosis (from undercooked meat or infected cat litter) and fungal species like candida. Treatment requires prescription medication, typically corticosteroid drops or stronger immunosuppressive therapy depending on the cause and severity.
Red Flags That Need Emergency Care
Most sore eyes improve with simple measures or resolve on their own. But a few patterns point to a medical emergency. Acute angle-closure glaucoma causes sudden, severe eye pain along with blurred vision, halos around lights, nausea or vomiting, and a visibly red eye. Permanent vision damage can happen rapidly without treatment. If you experience a combination of intense eye pain, nausea, and vision changes that come on suddenly, go to an emergency room.
Other warning signs that need urgent evaluation include sudden vision loss in one or both eyes, pain that develops after eye surgery or an eye injury, and eye soreness that gets progressively worse over hours rather than days.