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10 Causes of Pain in One Eye

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Last updated August 27, 2020

Eye pain questionnaire

Use our free symptom checker to find out what's causing your pain.

It's hard to ignore pain the eyes, as they are among the most sensitive of all our organs. Pain in one eye ranges in causes and severity, and has a variety of associated characteristics, such as swelling, fever, blurred vision, and more.

Eye pain questionnaire

Use our free symptom checker to find out what's causing your pain.

Eye pain symptom checker

Symptoms of pain in one eye

The eyes are among the most sensitive and important of all of our organs. If anything begins to go wrong with an eye, you will likely notice right away and become very protective of it.

Pain in only one eye is often a symptom of infection following some sort of trauma. Rubbing the eye when it feels dry or itchy can scratch the cornea, which is the clear tissue covering the surface of the eyeball. This will allow bacteria or other infectious agents to enter. [5,14] Eye infections can start suddenly and worsen quickly, so it is important to get professional care for symptoms of pain in one eye symptoms and not try to treat them yourself. [14]


Who is most often affected by pain in one eye?

  • Contact lens wearers.
  • Those who had chickenpox as a child.
  • Those who have had an autoimmune disorder, such as rheumatoid arthritis, ulcerative colitis, or type 1 diabetes.
  • Those who have had a metabolic disorder such as type 2 diabetes.
  • Those who have a serious systemic illness such as tuberculosis, because the infection can spread throughout the body and reach the eye.
  • Anyone with a weakened immune system from chemotherapy, radiation therapy, or AIDS.

Is pain in one eye serious?

  • A mild irritation that clears on its own within 24 hours is most likely not serious.
  • Localized redness, swelling, and mild pain in one eye is probably not a threat to sight, but should still be treated by a medical provider.
  • Sudden, severe pain with blurred vision and blank spots can be very serious and may lead to a loss of sight in one or both eyes.

Causes of pain in one eye

Causes include abnormal conditions involving the cornea, outlined in this section.

These are things that make the cornea susceptible to infectious agents:

  • Abnormal blinking, meaning the eyelids do not blink rapidly enough or close fully during blinking.
  • The cornea may become dry from lack of tears and normal moisture.
  • Degenerative disease of the cornea.
  • Use of steroid eyedrops.
  • Trauma, which can scratch or otherwise damage the cornea and allow infectious agents to get through it.
    • Acute injury.
    • Surgery.

An actual infection of the cornea, due to:

  • Bacteria.
    • Contact lenses.
      • Wearing lenses overnight or otherwise too long.
      • Improper cleaning and storage of lenses.
    • Infection of the eyelids that spreads to the damaged cornea.
  • Fungus.
    • This is usually from plant material (earth, grass, leaves, etc.) being blown into the eyes.
    • May also be due to contaminated contact lenses or solution.

Infection of the middle layer of the eye, which is often seen with:

A build-up of fluid within the eyeball (glaucoma)

Eye pain questionnaire

Use our free symptom checker to find out what's causing your pain.

Eye pain symptom checker

A flare-up of the virus that causes chickenpox.

  • If this occurs near the eye, it can interfere with vision.

Rare and unusual causes:

  • Immunocompromised cases, such that person's immune system has been weakened due to illness or treatments such as:
  • Chemotherapy.
  • Radiation therapy.
  • Acquired immune deficiency syndrome (AIDS) or HIV.

This list does not constitute medical advice and may not accurately represent what you have.

Foreign body in the eye

Foreign bodies like windblown grit, wood or masonry, or flecks of metal can land in the eye and get stuck there, causing extreme discomfort.

Rarity: Uncommon

Top Symptoms: feeling of something in the eye

Symptoms that always occur with foreign body in the eye: feeling of something in the eye

Urgency: In-person visit

Bacterial conjunctivitis

Bacterial conjunctivitis, or pinkeye, is an inflammation of the clear membranes covering the eye. It causes redness, pain, and irritation of one or both eyes.

Staphylococcus or streptococcus bacteria are often involved, and anything that brings bacteria to the eye can cause conjunctivitis. Touching the eyes with unwashed hands; sharing eye makeup, washcloths, or towels; or improperly cleaning contact lenses are common causes. The same bacteria that cause the sexually transmitted diseases chlamydia and gonorrhea can also cause conjunctivitis.

Most susceptible are children, but anyone can be affected.

Symptoms include a gritty, burning feeling in the eye; discharge or tears; swelling; itching; pink discoloration due to dilated blood vessels; and sensitivity to light.

Diagnosis is made through patient history, physical examination, and careful eye examination. Smears may be taken from the eye for testing.

Treatment involves a course of antibiotic eyedrops. It is important to use all of the drops as prescribed, even when the infection seems to improve. Warm compresses over the eyes can help ease the discomfort.

Rarity: Common

Top Symptoms: sore throat, eye redness, eye itch, watery eye discharge, eye redness

Symptoms that always occur with bacterial conjunctivitis: eye redness

Urgency: Primary care doctor

Vernal conjunctivitis

Vernal conjunctivitis is long-term (chronic) swelling (inflammation) of the outer lining of the eyes due to an allergic reaction. Vernal conjunctivitis often occurs in people with a strong family history of allergies, such as allergic rhinitis, asthma, and eczema.

Rarity: Ultra rare

Top Symptoms: wateriness in both eyes, eye itch, eye redness, sensitivity to light, feeling of something in the eye

Urgency: Primary care doctor

Corneal abrasion

Corneal abrasion is a wound to the part of the eye known as the cornea. The cornea is the crystal clear (transparent) tissue that covers the front of the eye. It works with the lens of the eye to focus images on the retina.

Rarity: Common

Top Symptoms: blurry vision, sensitivity to light, constant eye pain, moderate eye pain, pain in one eye

Symptoms that always occur with corneal abrasion: pain in one eye, wateriness in one eye, constant eye pain

Urgency: Phone call or in-person visit

Inflamed eyelid (blepharitis)

Inflamed eyelid, or blepharitis, is a bacterial infection of the skin at the base of the eyelashes.

If the oil glands around the eyelashes become clogged, normal skin bacteria will multiply in the oil and cause infection. The glands can become blocked due to dandruff of the scalp and eyebrows; allergies to eye makeup or contact lens solution; or eyelash mites or lice.

Symptoms include red, swollen, painful eyelids; oily, dandruff-like flakes of skin at the base of the eyelashes; and eyelashes that grow abnormally or fall out.

If the symptoms do not clear with hygiene, see a medical provider. Blepharitis can become chronic and lead to infections of the eyelids and cornea; dry eyes which cannot take contact lenses; and scarring and deformity of the eyelids.

Diagnosis is made through physical examination of the eyelids, under magnification and through skin swab of the eyelashes.

Treatment includes warm compresses and careful washing of the eyelids; antibiotics in pill or cream form; steroid eyedrops; and treatment for any underlying condition such as dandruff or rosacea.

Rarity: Common

Top Symptoms: eye itch, sensitivity to light, eye redness, feeling of something in the eye, dry eyes

Symptoms that never occur with inflamed eyelid (blepharitis): severe eye pain

Urgency: Self-treatment

Chronically dry eyes

Chronically dry eyes are a relatively common condition, especially in older adults, that can be very uncomfortable and lead to damage of the surface of the eye. They are caused by a decrease in the tear production of the eye or an increase in tear evaporation. Risk factors inc.

Contact lens-related eye infection

Millions of people wear contact lens daily without issue; however, there is a risk of infection. Often, infection is avoidable by keeping lenses clean.

Rarity: Rare

Top Symptoms: eye redness, wateriness in both eyes, sensitivity to light, constant eye redness, eye redness

Symptoms that always occur with contact lens-related eye infection: eye redness, constant eye redness

Urgency: In-person visit

Eye pain questionnaire

Use our free symptom checker to find out what's causing your pain.

Eye pain symptom checker

Acute close-angle glaucoma

Acute closed-angle glaucoma is also called angle-closure glaucoma or narrow-angle glaucoma. "Acute" means it begins suddenly and without warning.

"Glaucoma" means the fluid pressure inside one or both eyes is too high. "Closed-angle" means that the iris – the circular band of color in the eye – does not dilate open properly and blocks the natural drainage mechanism within the eye. The fluid builds up and causes the pressure to increase.

The exact cause of any glaucoma is not known. It may be an inherited trait.

Acute closed-angle glaucoma can be triggered by an extreme dilation of the eyes, as when walking from bright light into total darkness.

Symptoms include sudden eye pain, headache, nausea, blurred vision, and seeing a rainbow-like aura around lights. This is a medical emergency. Take the patient to the emergency room or call 9-1-1.

Diagnosis is made through patient history and thorough eye examination.

Treatment involves surgery to correct the dilation and drainage mechanisms of the eyes, as well as prescription eyedrops and oral medications.

Rarity: Rare

Top Symptoms: headache, nausea or vomiting, vision changes, being severely ill, eye pain

Urgency: Hospital emergency room

Anterior uveitis

Uveitis refers to any inflammatory condition that causes swelling and destroys the tissues of the middle layer of the eye. It can occur in people of all ages, but primarily affects people between the ages of 20 and 60 years old.

Uveitis may be the result of eye problems or diseases, or i.

Orbital cellulitis

Orbital Cellulitis is an uncommon condition in which an infection has breached or circumvented the outer portion of the eye and affected the tissues of the orbit, also known a..

Pain in one eye treatments and relief

Seek immediate pain in one eye treatment in the emergency room or call 911 if:

  • You have sudden, severe pain in one eye along with impaired vision, especially if there appears to be a spot on the surface of the eye. This is a medical emergency that can lead to permanent vision loss. Be sure to bring any contact lenses and cases with you, since the medical providers may want to culture them to find a possible organism causing the problem.

Schedule an appointment for:

  • A sore, reddened, irritated eye with moderate pain and some discharge. Bring any contact lenses and cases with you to the appointment.

Pain in one eye remedies that you can try at home:

  • For very mild symptoms you can use over-the-counter eyedrops, but if the symptoms do not clear up quickly you must visit a medical provider.
  • Be aware of the limitations of wearing contact lenses and learn the proper way to care for your lenses and cases.
  • Frequent and thorough hand washing, as well as touching your eyes as little as possible, will help greatly with avoiding any sort of eye infection.

Questions your doctor may ask about pain in one eye

  • Do you feel like there is something in your eye?
  • Have you noticed any vision changes?
  • Do your eyelids feel sticky?
  • Do you have dry eyes?

Self-diagnose with our free Buoy Assistant if you answer yes on any of these questions.

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Dr. Rothschild has been a faculty member at Brigham and Women’s Hospital where he is an Associate Professor of Medicine at Harvard Medical School. He currently practices as a hospitalist at Newton Wellesley Hospital. In 1978, Dr. Rothschild received his MD at the Medical College of Wisconsin and trained in internal medicine followed by a fellowship in critical care medicine. He also received an MP...
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