What Causes Eyeball Pain and When Is It Serious?

Eyeball pain ranges from a dull ache behind the eyes after a long day at a screen to a sharp, stabbing sensation that signals a genuine emergency. Most episodes trace back to something mundane, like a scratch on the cornea or tired eye muscles, but the same symptom can also be the first warning of conditions that threaten your sight within hours. The nerves responsible for eye pain are branches of the trigeminal nerve, one of the most sensitive neural pathways in the body, which is partly why even minor irritations can feel disproportionately alarming. Understanding the spectrum of causes, and the handful of red flags that separate a nuisance from an emergency, can help you respond appropriately.

How the Eye Senses Pain

The cornea, the clear front surface of the eye, is one of the most densely innervated tissues in the human body. Sensory nerve fibers from the trigeminal ganglion thread through the cornea, the conjunctiva, and the deeper structures of the eye, detecting mechanical, chemical, and thermal threats.¹ That density is a defense mechanism: you want to know immediately if something is in your eye or if tissue is being damaged. But it also means that very small insults, a grain of sand, a gust of dry air, can produce pain that feels out of proportion to the actual threat. Broadly, eye pain falls into two categories. Surface pain originates on or near the cornea and tends to feel gritty, burning, or sharp. Deep or orbital pain comes from behind the eye and often feels like pressure, aching, or throbbing. The distinction matters because surface pain usually points to the eye’s outer structures, while deep pain may involve the orbit, the optic nerve, or even referred pain from elsewhere in the head.

The Most Common Everyday Cause: Digital Eye Strain

If you spend hours staring at a phone, laptop, or monitor, you have probably experienced aching, tired eyes by the end of the day. Digital eye strain involves a cluster of symptoms: soreness behind the eyes, mild headache, blurry vision at a distance after prolonged near work, and a gritty feeling. The mechanism is straightforward. When you focus on a screen, your blink rate drops substantially, which destabilizes the tear film and dries the corneal surface. At the same time, the ciliary muscle inside the eye, which adjusts focus, stays contracted for long periods, producing fatigue similar to what you would feel in any muscle held in one position.² Digital eye strain is uncomfortable but not dangerous. It resolves with breaks, blinking, and adjusting your screen distance. It does not cause permanent damage, and if the pain is clearly tied to screen use and goes away when you stop, there is no reason for alarm.

Corneal Abrasions and Foreign Bodies

A corneal abrasion, a scratch on the surface of the eye, is one of the most common reasons people show up at an emergency room for eye pain. It can happen from a fingernail, a contact lens, a flying wood chip, or even vigorous rubbing. The pain is usually immediate and sharp, often accompanied by tearing, sensitivity to light, and a persistent sensation that something is stuck in the eye.³ Because the cornea is so richly supplied with nerve endings, even a tiny scratch can be agonizing. The good news is that minor abrasions usually heal on their own within a day or two. The corneal epithelium regenerates quickly. The concern with abrasions is secondary infection: a damaged cornea is vulnerable to bacteria, fungi, and other organisms that normally cannot penetrate the intact surface. If an abrasion does not improve within 24 to 48 hours, or if the pain worsens, redness increases, or discharge appears, you should see a clinician promptly.

Contact Lens Problems and Infectious Keratitis

Contact lenses sit directly on the cornea, and when something goes wrong with them, the consequences can be severe. Wearing lenses for too long, sleeping in them, rinsing them in tap water, or handling them with dirty hands all raise the risk of microbial keratitis, an infection of the cornea. Contact lens wear is the single biggest risk factor for ulcerative keratitis in developed countries.⁴

One especially concerning form is Acanthamoeba keratitis, an infection caused by a microscopic organism found in soil, tap water, and poorly maintained lens cases. In one clinical series, over 95 percent of Acanthamoeba keratitis cases occurred in contact lens wearers.⁵ The infection can initially mimic a simple abrasion or dry eyes, with mild discomfort and redness, which means it often goes undiagnosed until it has progressed. By the time it is caught, it can present as a deep corneal abscess requiring biopsy to confirm.⁶ If you wear contact lenses and develop eye pain that does not resolve after removing the lens, or if you notice increasing redness, light sensitivity, or blurred vision, get it evaluated quickly. Corneal infections that are caught early respond much better to treatment than those discovered late.

Dry Eye and the Shift to Chronic Pain

Dry eye disease is extraordinarily common, and many people dismiss the burning or stinging it causes as a minor annoyance. For most, it is. But in a subset of chronic dry eye sufferers, the pain persists even after tear production is restored or the ocular surface looks healthy under examination. Researchers have found that repeated irritation of the corneal nerve fibers can trigger a transition from normal, acute pain to chronic neuropathic pain, where the nerves themselves become the problem rather than the dry surface.⁷ In these cases, the brain keeps receiving pain signals even though the original cause has been addressed, a phenomenon called central sensitization. This is why some people with burning eye syndrome find that artificial tears and anti-inflammatory drops offer only partial relief. The pain has become a nerve disorder, not just a surface disorder. If you have been treating dry eye symptoms for months without improvement, a conversation with a specialist about neuropathic pain management may be worth pursuing.

Acute Angle-Closure Glaucoma

This is one of the true ophthalmologic emergencies. In acute angle-closure glaucoma, the fluid drainage pathway inside the eye becomes physically blocked, causing intraocular pressure to spike rapidly. The symptoms can be dramatic: severe eye pain, a rock-hard feeling to the eyeball, blurred vision, halos around lights, headache, nausea, and sometimes vomiting. The nausea and headache can actually mislead people into thinking they have a migraine or a stomach bug, delaying the correct diagnosis. In Europe, the incidence is roughly two to four cases per 100,000 people per year, so it is not common, but when it strikes, the elevated pressure can permanently damage the optic nerve within hours.⁸ If you experience sudden, severe eye pain with vision changes and nausea, go to an emergency room. The treatment involves lowering the pressure urgently, usually with medications followed by a laser procedure to open the drainage pathway.

Inflammation Inside the Eye

Several inflammatory conditions can cause deep, aching eye pain that worsens over hours to days. Anterior uveitis, inflammation of the iris and the surrounding structures, is one of the more common forms eye care providers encounter. It produces pain, redness, light sensitivity, and sometimes a small, irregular pupil. The causes are diverse: autoimmune diseases, infections, and sometimes no identifiable trigger at all.⁹ Left untreated, uveitis can cause scarring inside the eye, elevated pressure, and vision loss.

Scleritis, inflammation of the sclera (the white outer coat of the eye), tends to be more severe. The pain is often described as a deep, boring ache that can radiate to the forehead, cheek, or jaw, and it frequently wakes people up at night. Scleritis poses a real threat to vision and often signals an underlying systemic inflammatory disease.¹⁰ Eye involvement is, in fact, a common finding in systemic autoimmune conditions like rheumatoid arthritis, Sjögren syndrome, and certain forms of vasculitis.¹¹ If you already have a diagnosed autoimmune condition and develop new eye pain, that context matters and should be shared with your eye doctor immediately.

Optic Neuritis and Neurological Causes

Pain that occurs specifically with eye movement, especially when accompanied by a drop in vision in one eye and a change in color perception, raises concern for optic neuritis, inflammation of the optic nerve. The pain tends to be a dull ache behind the eye that worsens when you look around. Optic neuritis is significant not only because of the vision loss it can cause but because it is often the first clinical sign of multiple sclerosis.¹² Not every case of optic neuritis leads to a multiple sclerosis diagnosis, but the association is strong enough that neurologists typically order brain imaging when it is confirmed.

A less familiar cause of periocular pain is trochleodynia, a condition involving inflammation or dysfunction of the trochlea, a small pulley-like structure in the inner upper orbit that the superior oblique eye muscle runs through. It can produce a localized ache at the inner corner of the upper eye socket, sometimes mimicking a headache or sinus pain, and often goes unrecognized for a long time.¹³ If you have been dealing with a stubborn pain at the upper inner corner of your eye that no one can explain, trochleodynia is worth bringing up with a clinician.

Giant Cell Arteritis and Vascular Threats

For anyone over 50 who develops new eye pain, headache, scalp tenderness, or jaw pain while chewing, giant cell arteritis (GCA) should be on the radar. GCA is a vasculitis, an inflammation of blood vessel walls, that preferentially targets the temporal and ophthalmic arteries. The most feared complication is permanent vision loss from ischemic optic neuropathy, which occurs when inflamed arteries cut off blood supply to the optic nerve.¹⁴ In a population-based cohort study, ischemic optic neuropathy was the most common eye-related diagnosis in GCA patients, and vision loss from anterior ischemic optic neuropathy was far less likely to recover compared with other visual complications.¹⁵

The critical point is that once ischemia has occurred, the damage is generally permanent. The same cohort data confirmed that vision loss persists even in treated patients once tissue ischemia has set in.¹⁵ Treatment with high-dose corticosteroids needs to begin immediately, sometimes before biopsy confirmation, because waiting even a day can mean the difference between saving and losing sight. When a patient over 50 has both ischemic optic neuropathy and a central retinal artery occlusion, the working diagnosis should be GCA until proven otherwise.¹⁴

Post-Surgical Eye Pain

Eye pain after surgery is expected in the first day or two, but certain patterns should raise concern. After cataract surgery, the most serious complication to watch for is endophthalmitis, an infection inside the eye. Symptoms include worsening pain, redness, and sometimes purulent discharge, along with declining vision.¹⁶ Endophthalmitis is rare, but it constitutes an emergency that can lead to loss of the eye if not treated aggressively with antibiotics and, often, additional surgery.

Refractive procedures like LASIK can also produce lingering pain. The laser reshapes the cornea by cutting a flap and ablating tissue underneath, which severs corneal nerve fibers. For most patients, those nerves regenerate within a few months. But in some cases, the nerves do not heal properly, leading to chronic pain, light sensitivity, and burning that begin within weeks of the procedure and persist well beyond the normal recovery window.¹⁷ This corneal neuralgia after LASIK is uncommon but can be debilitating and difficult to treat, since the underlying problem is nerve dysfunction rather than a surface abnormality. If eye pain after any surgery is worsening rather than improving with each passing day, that trajectory alone warrants a call to the surgeon.

Eye Pain in Young Children

When a preschooler complains of eye pain, the diagnostic challenge is different. Young children often cannot describe what they feel with precision, and many of them struggle to distinguish between eye pain and vague visual symptoms. A study looking at eye pain in preschool children found that, in the absence of an obvious external cause like a scratch or a visible foreign body, the complaint was usually functional rather than a sign of a serious eye disease.¹⁸ That said, “functional” does not mean fabricated; it means the child is perceiving discomfort without a structural problem. It is still worth having a pediatrician or pediatric ophthalmologist check the child, especially if the complaint is persistent, if there is visible redness or swelling, or if the child is squinting, rubbing the eye constantly, or avoiding light. Serious causes of eye pain in children, such as juvenile uveitis, do exist, and they can be sight-threatening if missed. The difference from adults is simply that the base rate of harmless causes is higher in this age group.

When to Treat at Home and When to Get Help

Not every episode of eye pain requires a doctor’s visit. Here are some general guidelines for sorting mild from potentially serious situations:

• Likely safe to monitor: Mild achiness or gritty feeling that follows prolonged screen use, dry indoor air, or a windy day. Improves with rest, lubricating drops, and breaks from near work.
• Worth a routine appointment: Persistent dryness or burning that does not respond to over-the-counter artificial tears after a week or two. Mild discomfort with contact lens wear that resolves when lenses are removed but keeps coming back. A foreign body sensation after a known minor scratch that is improving day by day.
• See someone soon, within a day or two: Eye pain with new redness, light sensitivity, or blurred vision. Pain that started after a contact lens felt wrong. A scratched eye that is not improving within 24 to 48 hours, or one that is getting worse.
• Emergency, same day or immediately: Sudden severe eye pain with nausea, halos around lights, or a visibly red, hard eye. Pain with significant vision loss in one eye. Eye pain with movement plus color vision changes. New eye pain with scalp tenderness, jaw claudication, or unexplained weight loss in someone over 50. Worsening pain, redness, and declining vision after recent eye surgery.

The conditions that demand urgency, like acute angle-closure glaucoma, endophthalmitis, and giant cell arteritis, all share a common feature: delaying treatment by even a few hours can mean the difference between keeping and losing vision. When in doubt, erring on the side of getting checked is the rational move, because the worst-case scenario with a false alarm is an unnecessary trip to the eye doctor, while the worst case with a missed emergency is irreversible blindness.

Referred Pain and the Headache Overlap

Eye pain is not always about the eye. The trigeminal nerve, which relays sensation from the eye, also covers the forehead, sinuses, teeth, and jaw. This shared wiring means that problems in those areas can produce pain that feels like it is coming from the eyeball. Sinus infections are a classic culprit: pressure behind or around the eye that worsens when you bend forward. Migraines and cluster headaches frequently involve pain centered on or behind one eye, sometimes with tearing and nasal congestion that mimic eye disease. Tension in the muscles around the orbit, including the trochlear mechanism mentioned earlier, can create a focused ache that convinces you the problem is inside the eye when it is actually in the surrounding tissue.¹³ A useful self-check is to close the painful eye and gently press on the skin around the orbit. If the tenderness is in the bony rim, the brow, or the inner corner of the socket rather than in the eyeball itself, the problem may be musculoskeletal or sinus-related rather than ocular. Of course, even referred pain can coexist with actual eye disease, so the self-check is a clue, not a diagnosis.