Eye Pain: What's Important to Know

Eye pain is a symptom, not a diagnosis in itself. The International Classification of Diseases, 10th revision, lists the code H57.1 for eye pain, but in real-world practice, the cause of the pain is far more important than the code itself: superficial corneal irritation, choroidal inflammation, increased intraocular pressure, scleral inflammation, neuro-ophthalmological disease, orbital process, trauma, or chemical injury. [1]

The clinical significance of this symptom is that various causes can appear similar in the first few hours. The patient may describe "ache in the eye," "pressure behind the eye," "gritty," "burning," "shooting," or "pain when moving the eye," but these complaints conceal conditions with fundamentally different urgency: from dry eye syndrome to a vision-threatening attack of angle closure or infectious keratitis. [2]

Eye pain can be conveniently divided into four broad categories. The first is superficial pain, most often associated with the cornea and conjunctiva. The second is deep intraocular pain, characteristic of uveitis and acutely elevated intraocular pressure. The third is scleral and orbital pain, often described as deep, boring, or bursting. The fourth is neuro-ophthalmological and referred pain, such as with optic neuritis, certain headaches, or sinus-orbital processes. [3]

The most dangerous mistake is judging the severity of the condition solely by pain intensity. Severe pain is indeed typical for keratitis, scleritis, and acute attacks of angle closure, but the severity of the symptom does not always linearly reflect the severity of the injury. Sometimes, it's not the intensity that is decisive, but the combination of pain with decreased vision, photophobia, halos around lights, nausea, vomiting, eyelid swelling, proptosis, or pain with eye movement. [4]

Another important principle: not all pain around the eye is a disease of the eyeball itself. A normal ophthalmological examination should also consider migraines, cluster headaches, neuralgia, sinusitis, orbital conditions, and other neurological causes. Therefore, a competent article on the topic should explain not only "what causes eye pain" but also how to distinguish a true ophthalmological emergency from periorbital pain and pain associated with normal ocular status. [5]

Table 1. Red flags for eye pain

Sign	What could be hidden?	Tactics
Decreased visual acuity	keratitis, uveitis, acute angle closure attack, optic neuritis, severe trauma	urgent ophthalmologist examination
Severe pain and severe photophobia	keratitis, anterior uveitis, scleritis	same day inspection
Rainbow circles, nausea, vomiting, sore red eye	acute attack of anterior chamber angle closure	urgent Care
Wearing contact lenses with pain and redness	microbial keratitis	urgent examination within 24 hours, often faster
Recent injury	erosion, foreign body, rupture of membranes, hyphema, orbital trauma	urgent assessment
Chemical exposure	eye burn	immediate lavage and emergency care
Pain when moving eyes, decreased color vision	optic neuritis, orbital process	urgent examination
Proptosis, fever, limited movement	orbital cellulitis, orbital formation	emergency hospitalization

The table is compiled based on modern materials on “red eye”, acute closure of the anterior chamber angle, chemical injuries and optic neuritis. [6]

When emergency help is needed

A situation where pain is combined with decreased vision should be considered an emergency. This combination of symptoms is far more serious than simply redness or discomfort. Decreased visual acuity, along with pain and photophobia, is considered one of the primary signs of a potentially sight-threatening condition in the initial triage. [7]

A special case is acute anterior chamber angle closure. It is characterized by sudden, severe pain, blurred vision, halos or rainbow-like rings around lights, headache, nausea, and vomiting. This is one of the few ophthalmologic emergencies in which irreversible damage to the optic nerve can develop very quickly, so waiting "until tomorrow" is unacceptable. [8]

Microbial keratitis is no less dangerous, especially in contact lens wearers. It often presents with unilateral pain, redness, severe photophobia, discharge, corneal clouding, and visual impairment. Such patients should discontinue contact lens wear immediately and seek urgent examination, as delay increases the risk of corneal ulceration, scarring, perforation, and permanent vision loss. [9]

Chemical eye burns are a separate category, where treatment begins even before arrival at the clinic. The key action is immediate and copious irrigation with any available clean solution or water, without waiting for an examination or preliminary formalities. In the hospital, irrigation is continued until the ocular surface pH returns to normal, as the speed and completeness of irrigation have the greatest impact on the outcome. [10]

Patients with pain with eye movement, sudden loss of color vision, proptosis, fever, limited ocular movement, or severe trauma also require urgent referral. Optic neuritis, orbital cellulitis, ruptured ocular membranes, foreign bodies, and other conditions that can make the process truly time-consuming must be ruled out. [11]

Table 2. When emergency care is needed and when urgent same-day examination is needed

Situation	Probable urgency
Chemical burn	immediately, with rinsing before examination
Suspected acute attack of anterior chamber angle closure	immediately
Severe eye injury, deformed eye, blood in the anterior chamber	immediately
Pain in a contact lens wearer with visual impairment	very urgent, same day
Severe photophobia and ciliary injection	on the same day
Pain when moving the eyes and sudden deterioration of vision	urgently
Mild dryness, burning, discomfort without red flags	planned after eliminating dangerous causes

The table is based on current guidelines for emergency ophthalmology and the initial evaluation of painful red eye.[12]

The main causes of pain in the eye area

The most common and relatively benign group of causes are diseases of the ocular surface. Dry eye syndrome can cause irritation, burning, soreness, a feeling of dryness, "gritty" eyes, occasional blurred vision, and intermittent photophobia. With more severe damage to the surface, discomfort becomes more than just "dryness" but a full-blown pain complaint. [13]

Corneal erosions and foreign body lesions also belong to the same superficial group. These are characterized by acute, aching pain, lacrimation, a foreign body sensation, and worsening symptoms with blinking. Recurrent erosions often occur in the morning upon opening the eyes after sleep, especially if there was a previous injury from a fingernail, paper, or other sharp object. [14]

The next major group are infectious corneal lesions, primarily microbial keratitis. This is no longer an "irritation," but a potentially sight-threatening condition. It is often associated with contact lenses, corneal trauma, or a compromised corneal barrier. Clinically, unilateral pain, photophobia, severe redness, discharge, corneal infiltrate or clouding, and decreased vision are alarming. [15]

Anterior uveitis causes deeper pain. It is characterized by redness, photophobia, blurred vision, and a dull or throbbing ache associated with spasm of the ciliary muscle and irritation of the ciliary nerves. Unlike superficial pain, this type of pain is less like "sand" and more like internal inflammatory pressure. Furthermore, anterior uveitis may be associated with systemic inflammatory diseases and is prone to recurrence. [16]

Scleritis is one of the most important causes of severe, profound pain. It is characterized by constant pain, often at night, tenderness with eye movement, and often decreased vision. Severe forms are often associated with systemic autoimmune diseases. Therefore, scleritis requires not only a local examination but also a search for a systemic inflammatory pathology. [17]

Finally, neuro-ophthalmological and non-ophthalmological causes must be considered. With typical optic neuritis, pain often intensifies with eye movement, and later, visual impairment and color perception disturbances are added. With cluster headaches and some migraines, pain can be localized around the eye and accompanied by lacrimation, redness, and autonomic symptoms, although there may be no actual severe ocular disease. [18]

Table 3. Common causes of pain according to clinical picture

Clinical drawing	More likely reasons
Burning, dryness, sand, intermittent fogging	dry eye syndrome
Scratching pain, tearing, pain when blinking	corneal erosion, foreign body
Unilateral pain, photophobia, corneal opacity, contact lenses	microbial keratitis
Dull deep pain, photophobia, ciliary injection	anterior uveitis
Severe deep pain, worse at night and when moving the eyes	scleritis
Sudden pain, halos, nausea, vomiting	acute attack of anterior chamber angle closure
Pain when moving the eyes, deterioration of color perception	optic neuritis
Paroxysmal pain around the eye with lacrimation and vegetative symptoms	cluster headache, less commonly migraine

The table is compiled based on modern guidelines and reviews on corneal, inflammatory, glaucoma and neuro-ophthalmological pathology. [19]

Diagnostics

A proper diagnosis begins not with equipment, but with a few simple questions. It's important to determine when the pain began, whether it's constant, whether it intensifies with blinking or eye movement, whether there's decreased vision, discharge, contact lenses, trauma, chemical exposure, autoimmune diseases, headache, nausea, or vomiting. Even at this stage, it's possible to determine whether the problem is more likely to be superficial, intraocular inflammation, glaucoma, a neuro-ophthalmological condition, or an orbital process. [20]

The first thing a doctor must assess is visual acuity. This is a basic indicator of severity, not an optional step. Modern literature on "red eye" and painful eye clearly emphasizes that decreased visual acuity is a key warning sign and helps differentiate relatively benign conditions from those that are potentially sight-threatening. [21]

The next critical step is examination of the anterior segment of the eye. Fluorescein staining is particularly informative for superficial lesions, helping to identify erosions, epithelial defects, and some ulcerative changes in the cornea. If a corneal ulcer or microbial keratitis is suspected, the physician assesses the presence of infiltrate, edema, and anterior chamber reaction and considers microbiological examination of the specimen. [22]

If the clinical picture resembles an acute attack of angle closure, an urgent assessment of intraocular pressure and angle anatomy is necessary, as well as an examination of the cornea, pupil, and anterior chamber. The goal here is not simply to "confirm the diagnosis," but to initiate pressure reduction as quickly as possible and prepare the patient for more definitive intervention after stabilization. [23]

When pain occurs with eye movement and vision loss occurs, the logic changes: optic neuritis and orbital processes must be considered. In this situation, magnetic resonance imaging of the orbits and brain with contrast is essential, as it not only helps confirm inflammation of the optic nerve but also searches for signs of demyelinating disease or other atypical causes. [24]

If scleritis and systemic inflammation are suspected, diagnostic workup extends beyond the eye. The physician collects a rheumatological history and may order targeted laboratory tests, including antineutrophil cytoplasmic antibodies and antinuclear antibodies. In the case of posterior scleritis, ultrasound, computed tomography, or magnetic resonance imaging may be added. This is important because eye pain in this case may be the first clinical marker of a systemic disease. [25]

Table 4. Main diagnostic methods and their role

Method	What helps to identify
Visual acuity test	severity of the condition, presence of a vision-threatening process
Fluorescein staining	erosions, epithelial defects, some ulcerative lesions
Biomicroscopy	anterior segment inflammation, infiltrates, cells and protein in the anterior chamber
Measuring intraocular pressure	suspected acute attack of angle closure and other glaucoma conditions
Microbiological examination of the cornea	clarification of the pathogen in case of suspected infectious keratitis
Magnetic resonance imaging of the orbits and brain	optic neuritis, orbital processes, atypical pathology
Ultrasound, computed tomography, magnetic resonance imaging	posterior scleritis, orbital pathology, trauma

The table is based on current ophthalmological and neuro-ophthalmological guidelines.[26]

Differential diagnosis

The most useful practical distinction is between superficial and deep pain. Superficial pain is typically felt as aching, burning, scratching, discomfort when blinking, and a foreign body sensation. Deep pain is more often described as aching, pressing, boring, or throbbing, is worse at night, and may be aggravated by eye movement. [27]

If pain is accompanied by severe photophobia and redness around the cornea, keratitis and anterior uveitis are the prime candidates. If there is discharge, an epithelial defect, a corneal infiltrate, contact lenses, or previous trauma, the likelihood of keratitis increases. If deep pain, miosis, anterior chamber reaction, and a history of inflammatory diseases predominate, anterior uveitis is more likely. [28]

Scleritis must be distinguished from episcleritis. Episcleritis is typically less painful and often has a milder course, whereas scleritis causes true, deep pain, often pain with eye movement, poorer nocturnal symptom control, and a higher risk of systemic association. This distinction is essential for editorial purposes because patients and even primary care physicians frequently confuse these two conditions. [29]

An acute attack of angle closure differs from other causes in that the pain quickly becomes intense, vision becomes blurred, halos around lights appear, headache, nausea, and vomiting occur. This combination of symptoms is poorly explained by dry eye, episcleritis, or simple corneal erosion, but is very characteristic of a sharp increase in intraocular pressure. [30]

If the eye examination is normal or nearly normal, but pain occurs with eye movement and vision deterioration, especially color vision, optic neuritis should be considered. Recurring paroxysmal periorbital pain with autonomic symptoms should prompt consideration of cluster headache. Thus, severe pain around the eye does not always indicate corneal or conjunctival disease, and this is precisely why a comprehensive differential diagnosis is so valuable. [31]

Table 5. What are the differences between the main disease states?

State	Key type of pain	What else is characteristic?
Dry eye syndrome	burning, discomfort	dryness, sand, intermittent fogging
Corneal erosion	sharp scratching	pain when blinking, lacrimation
Microbial keratitis	pronounced painful	photophobia, infiltrate, decreased vision, lenses
Anterior uveitis	dull deep	photophobia, ciliary injection, blurring
Scleritis	deep drilling	worse at night, pain when moving eyes
Acute attack of angle closure	very strong pressure	halos, nausea, vomiting, blurred vision
Optic neuritis	pain when moving eyes	decreased vision, impaired color perception
Cluster headache	paroxysmal around the eye	lacrimation, autonomic symptoms, normal ocular examination

The table is compiled from corneal, uveal, glaucoma and neuro-ophthalmological sources. [32]

Treatment

Treatment is always determined by the cause, not just the presence of pain. The primary goal is not simply to alleviate the symptom, but to preserve the cornea, optic nerve, and visual function. Therefore, in vision-threatening conditions, pain relief should never replace specialized care. [33]

For dry eye syndrome, a modern step-by-step approach begins with patient education, environmental modifications, reducing tear film evaporation, artificial tears, and other methods of restoring the ocular surface. For more severe cases, treatment is selected phenotypically and stepwise, as the same symptom of "eye pain" can be a manifestation of both evaporative and water-deficient dry eye. [34]

For corneal erosions, gentle pain relief and epithelial protection are essential. Current primary care guidelines recommend simple oral pain relief and moisturizers rather than the uncontrolled use of topical anesthetics at home. The latter may indeed reduce pain, but when used unsupervised, they increase the risk of poor healing, infection, scarring, and even vision loss. [35]

For microbial keratitis, topical antibacterial agents remain the mainstay of treatment, and many cases of small extracentral ulcers resolve with empirical therapy. However, this does not mean the condition can be treated on its own. Contact lens wearers and those suspected of having a corneal ulcer require urgent examination, and in some cases, microbiological confirmation of the causative agent is necessary. If a lens wearer has a traumatic erosion, antibiotic prophylaxis is also important to prevent acute infection. [36]

Anterior uveitis is typically treated with topical corticosteroids, with cycloplegic agents added to reduce pain and photophobia by relieving ciliary muscle spasm and preventing posterior synechiae. Chronic or recurrent cases may require a stepwise increase in therapy and a search for a systemic inflammatory disease. Scleritis is treated differently: in modern literature, corticosteroids are considered the mainstay of therapy, with immunosuppressive and biological agents added when necessary. [37]

In acute angle closure, intraocular pressure should first be rapidly reduced with medication, followed by a more permanent anatomical solution, most often laser peripheral iridotomy, when the condition of the cornea and anterior segment allows. In typical optic neuritis, treatment is not always necessary: according to the North American Society of Neuro-Ophthalmology, steroid therapy accelerates recovery but does not improve the final visual outcome in typical forms; however, isolated administration of medium-dose prednisone without prior intravenous administration may increase the risk of relapse. [38]

Table 6. Treatment depending on the cause

Cause	Basic tactics
Dry eye syndrome	Tear substitutes, environmental correction, step-by-step treatment of the ocular surface
Corneal erosion	pain relief, epithelial protection, physician supervision
Microbial keratitis	urgent examination, local antibacterial drugs, sometimes culture
Anterior uveitis	topical corticosteroids, cycloplegics, search for the cause
Scleritis	systemic anti-inflammatory therapy, sometimes immunosuppression
Acute attack of angle closure	immediate pressure reduction, then laser peripheral iridotomy or other intervention
Optic neuritis	case assessment, magnetic resonance imaging, steroid decision based on indications
Chemical burn	immediate irrigation until acidity is normalized, emergency ophthalmological care

The table is compiled according to modern ophthalmological and neuro-ophthalmological guidelines. [39]

Prevention and prognosis

Prevention depends on the cause. For ocular surface diseases, a proper visual stress regimen, dry air control, sufficient blinking when working with a screen, eyelid care, and prompt treatment of dry eyes are crucial. It seems trivial, but it is the superficial instability of the tear film that often turns mild discomfort into chronic eye pain. [40]

Proper contact lens hygiene is especially important for the prevention of microbial keratitis. Recent clinical studies and reviews reaffirm that contact lenses remain a major risk factor for this condition. Sleeping in lenses without a doctor's approval, not replacing lenses on time, using a contaminated lens case, and continuing to wear lenses despite pain or redness significantly increase the risk of severe infection. [41]

Chemical injuries are largely prevented by protective equipment and prompt action in the event of an accident. When working with household chemicals, solvents, construction mixtures, and aggressive liquids, protective goggles remain the most effective preventative measure. If contact has already occurred, the only appropriate first step is immediate rinsing. [42]

The prognosis for eye pain also depends entirely on the cause and the speed of correct treatment. Dry eyes and uncomplicated erosions often have a favorable prognosis. With typical optic neuritis, vision begins to recover in most patients within a few weeks, and 92% regain most of their visual function, although some patients continue to notice more subtle visual and color vision defects. [43]

The prognosis is worse with delayed treatment of acute angle-closure syndrome, microbial keratitis, involvement of deep ocular structures, severe scleritis, and chemical burns. For anterior uveitis, the reassuring formula "it will go away on its own" also cannot be used: in modern observations, a significant proportion of eyes with uveitis eventually develop complications, including cataracts and glaucoma. Therefore, the main prognosis for eye pain is very simple: the sooner the exact cause is identified, the higher the chance of preserving vision. [44]

FAQ

Can eye pain occur without redness?
Yes. This can happen, for example, with typical optic neuritis and some neurological or headache syndromes. The absence of intense redness does not automatically make the situation safe, especially if there is pain with eye movement and decreased vision. [45]

Can the cause of pain be determined by the fact that it intensifies with blinking?
Often, yes. Intensification with blinking is more typical of superficial pathology of the cornea and conjunctiva, such as erosion or a foreign body. However, this rule is not absolute, so if vision is impaired or photophobia is severe, an examination is required. [46]

Is pain in a contact lens wearer dangerous if the eye is only slightly red?
Yes, because even early microbial keratitis may not present a dramatic onset. Pain, photophobia, contact lenses, and even moderate visual impairment are sufficient grounds for an urgent evaluation. [47]

Why is the pain so profound with uveitis and scleritis?
Because these conditions involve inflammation of the deeper, more sensitive structures of the eye. In uveitis, irritation of the ciliary nerves and spasm of the ciliary muscle play a significant role, while in scleritis, it's inflammation of the sclera itself, often associated with a systemic immune process. [48]

Can I use pain-relieving drops at home if I'm experiencing severe pain?
For regular self-administration, no. Recent reviews warn that uncontrolled use of topical anesthetics can impair corneal healing and increase the risk of serious complications. [49]

When is magnetic resonance imaging especially necessary?
When there is a suspicion of optic neuritis, an atypical presentation, pain with eye movement, visual impairment, or the need to assess the risk of demyelinating disease. In such cases, neuroimaging becomes not an additional, but a key part of the evaluation. [50]

Key points from experts

Guillermo Amescua, MD, professor of clinical ophthalmology and medical director of the Ocular Surface Disease Program at the Bascom Palmer Eye Institute, works at the intersection of corneal pathology, scleritis, ocular surface disease, and chemical burns. His professional profile well reflects the central clinical thesis on this topic: superficial ocular pain should not be automatically dismissed as a "minor" issue, because ocular surface disease, corneal disease, and burns often determine the visual outcome in the first hours and days. [51]

Michelle K. Rhee, MD, clinical professor of ophthalmology at Mount Sinai School of Medicine, a corneal specialist, and co-author of the current American Academy of Ophthalmology guideline on bacterial keratitis, actually emphasizes the second key point: a sore eye in a contact lens wearer should always be considered for microbial keratitis before reassuring the patient with a diagnosis of irritation. [52]

Poemen Pui-Man Chan, MD, PhD, a representative of the Chinese University of Hong Kong, a participant in the World Glaucoma Association consensus meetings, and an author of the 2025 consensus statement on acute primary attack of angle closure, emphasizes the third pillar: rainbow halos, nausea, vomiting, and sudden eye pain are not a “headache with an eye,” but a typical signal of a possible glaucoma attack, which requires immediate pressure relief and subsequent ongoing intervention. [53]

Jeffrey L. Bennett, MD, PhD, a neuro-ophthalmologist and neuroimmunologist at the University of Colorado whose clinical interests include optic nerve diseases, optic neuritis, and demyelinating diseases, helps reinforce another important point: eye pain may be the first manifestation not of corneal pathology but of optic nerve inflammation, and in this situation, neuro-ophthalmologic evaluation and magnetic resonance imaging, rather than eye drops, are crucial. [54]