Eye pain has dozens of possible causes, ranging from something as minor as a dry patch on the surface to something as serious as a sudden pressure spike inside the eye. The location, type, and timing of the pain are the best clues to what’s going on. A sharp, gritty sting usually points to a surface problem, while a deep, dull ache behind the eye suggests something internal or even a cause outside the eye entirely.
Surface Pain vs. Deep Pain
The first useful distinction is whether the pain feels like it’s on the surface of your eye or deeper inside. Surface pain typically involves the cornea (the clear front layer), the conjunctiva (the thin membrane covering the white of the eye), or the eyelid. It tends to feel sharp, stinging, gritty, or burning. Deep or orbital pain feels like pressure or aching behind or around the eye and can involve the muscles, nerves, or internal structures.
Surface pain is far more common. It’s the kind you get from a stray eyelash, overworn contact lenses, or an eye that’s dried out from hours of screen time. Deep pain is less common but more likely to signal something that needs medical attention, especially if your vision changes at the same time.
Scratches on the Cornea
A corneal abrasion, or scratch on the surface of the eye, is one of the most painful eye injuries you can get, despite being relatively minor. A fingernail, a tree branch, a piece of dust that gets rubbed into the eye: any of these can scrape the cornea. The pain is intense, stays present even when your eyes are closed, and comes with extreme sensitivity to light. Many people instinctively want to keep the eye shut or stay in a dark room. Excessive tearing is another hallmark, often running down the cheek continuously, and the scratch can even trigger a runny nose.
The good news is that most corneal abrasions heal on their own within about 24 hours. If the pain hasn’t improved after a day, you should have it looked at to make sure the scratch hasn’t developed into an ulcer, which is a more serious open wound on the cornea that can affect vision.
Infections and Pink Eye
Eye infections present differently from a scratch. Pink eye (conjunctivitis) is the most common, and its signature symptom is itching rather than sharp pain. You might notice some light sensitivity, but it won’t be as severe as with an abrasion. The eye looks red, may feel slightly sore, and often produces a sticky discharge, especially overnight.
Most cases of pink eye are viral and resolve on their own within about two weeks. Bacterial pink eye, however, needs antibiotic treatment, so it’s worth having an eye doctor confirm which type you’re dealing with. The distinction matters because untreated bacterial infections can damage the surface of the eye.
Something Stuck in the Eye
Foreign bodies are among the most common causes of sudden eye pain. A speck of metal, wood, sand, or even a tiny insect can lodge under the eyelid or on the cornea itself. The pain is immediate and persistent, and blinking tends to make it worse because the eyelid drags across the object with each blink.
Small surface debris can sometimes be flushed out with clean water or saline. If you can see the particle sitting on the white of the eye, gentle irrigation may be enough. But if the object is embedded in the cornea or you can feel it but can’t see it, don’t try to dig it out. Rubbing or pressing on the eye can push it deeper. A doctor can remove embedded particles safely using specialized instruments under magnification. If you have any reason to think something punctured the eye rather than just landing on it, that’s a medical emergency.
Contact Lens Problems
If you wear contact lenses and your eye hurts, the lenses themselves are a likely culprit. Wearing contacts too long, sleeping in them, or not cleaning them properly increases the risk of a condition called microbial keratitis, where bacteria, fungi, or other organisms infect the cornea. Symptoms include redness, pain that persists even after removing the lens, light sensitivity, sudden blurry vision, and unusual discharge or wateriness.
Microbial keratitis is serious. In the worst cases it can lead to permanent vision loss or the need for a corneal transplant. Milder contact lens complications like dry eyes, minor corneal scratches, or general irritation (sometimes called contact lens-induced acute red eye) are more common and typically resolve by taking a break from wearing lenses. But any pain that continues after you’ve removed the lens warrants a call to your eye doctor, because you can’t easily tell the difference between mild irritation and an early infection on your own.
Internal Inflammation
Uveitis is inflammation inside the eye, and it causes a distinct combination of symptoms: eye pain, redness, light sensitivity, blurred vision, and dark floating spots drifting across your field of vision. It can affect one or both eyes and sometimes develops gradually enough that people delay getting help.
That delay is risky. Left untreated, uveitis can lead to retinal swelling, glaucoma, cataracts, optic nerve damage, retinal detachment, and permanent vision loss. If you have eye pain along with floaters or blurring, particularly in one eye, it’s worth being seen promptly. Uveitis is treatable, but the complications of ignoring it are not always reversible.
Acute Glaucoma
Acute angle-closure glaucoma happens when fluid pressure inside the eye spikes suddenly because the drainage pathway gets blocked. It causes severe eye pain, often with nausea or vomiting, halos around lights, and a rapid decline in vision. The eye may look red and the cornea can appear hazy or cloudy. This is a true emergency. Without treatment within hours, the pressure can permanently damage the optic nerve.
Acute glaucoma is more common in people who are farsighted, older adults, and those of East Asian descent. If you experience sudden intense eye pain with nausea and visual changes, get to an emergency room.
Pain When You Move Your Eye
If the pain isn’t constant but flares up specifically when you look around, that pattern points to a few possibilities. The most notable is optic neuritis, inflammation of the nerve that connects the eye to the brain. Most people with optic neuritis describe a dull ache behind the eye that gets worse with eye movement, along with temporary vision loss in one eye. Colors may appear washed out, and central vision can blur or dim over days.
Optic neuritis is significant because it’s sometimes the first sign of multiple sclerosis, though it can also occur on its own or after a viral infection. Vision usually recovers over weeks to months, but the condition needs evaluation to determine whether something broader is going on.
Pain That Comes From Outside the Eye
Not all eye pain originates in the eye. Cluster headaches cause extreme, stabbing pain in or behind one eye, often accompanied by redness, tearing, a drooping eyelid, and a stuffy or runny nose on the same side. A single attack typically lasts 30 to 45 minutes and ends as abruptly as it started. People experiencing a cluster headache are often unable to sit still and may pace or rock back and forth because the pain is so severe.
Migraines can also produce pain around or behind the eye, usually alongside throbbing on one side of the head, nausea, and sensitivity to light and sound. Sinus infections are another common source of referred eye pain, typically felt as pressure around the brow, cheeks, and bridge of the nose that worsens when you lean forward.
When Eye Pain Is an Emergency
Most eye pain turns out to be something treatable and temporary. But certain combinations of symptoms signal a need for immediate care:
- Sudden vision changes alongside the pain
- Severe pain with headache, fever, or intense light sensitivity
- Nausea or vomiting with eye pain
- Halos around lights appearing suddenly
- Swelling in or around the eye
- Inability to move the eye or keep it open
- Blood or pus coming from the eye
- Chemical splash or object impact to the eye
Any of these warrants emergency evaluation. For isolated, mild eye pain without vision changes, scheduling an appointment within a day or two is generally reasonable, especially if you can identify an obvious trigger like dry air, long screen use, or a new pair of contacts.