Corneal Ulcer

A corneal ulcer is an open sore on your cornea. Infection is the leading cause. Symptoms include a red, watery and bloodshot eye; severe eye pain and pus or other eye discharge. A corneal ulcer can lead to vision loss and blindness. It’s considered a medical emergency. Contact your eye care provider right away if you have symptoms of a corneal ulcer.


A corneal ulcer appears as white, hazy spots on the eye.
A corneal ulcer appears as white, hazy spots on the eye. This corneal ulcer is a bacterial infection related to sleeping in contact lenses.

What is a corneal ulcer?

A corneal ulcer is an open sore on your cornea. Your cornea is the dome-shaped clear tissue layer that covers the front of your eye. Infection is the most common cause of a corneal ulcer.


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Who gets a corneal ulcer?

You’re at risk of a corneal ulcer if you:

  • Wear contact lenses, especially if you sleep in your contacts.
  • Have or have had shingles, cold sores or chickenpox.
  • Have dry eyes.
  • Have eyelids that don’t close all the way.
  • Use steroid eye drops.
  • Have an injury or burn on your cornea.
  • Have diabetes.
  • Have had prior eye surgery.
  • Have other eye diseases.

How common are corneal ulcers?

In the U.S., between 30,000 and 75,000 corneal ulcers occur each year. About 12% of all corneal transplants are done due to a corneal ulcer.


Is a corneal ulcer serious?

A corneal ulcer can cause permanent damage, even blindness if it’s not treated. If you think you have a corneal ulcer or have any eye problems that bother you, contact your eye care provider right away.

Symptoms and Causes

What are the symptoms of a corneal ulcer?

Symptoms of a corneal ulcer include:

  • Red, teary, bloodshot eye.
  • Eye pain (can be severe), eye ache.
  • Pus or other eye discharge.
  • A feeling like there’s something in your eye.
  • Light hurts your eye.
  • Blurred vision.
  • Swollen eyelids.
  • A white or gray spot or area on your cornea. (Some ulcers are too small to see. Your provider can see it during an eye exam.)

A corneal ulcer usually develops in one eye only.


Is a corneal ulcer a medical emergency?

Because a corneal ulcer can cause permanent vision loss, rupture your cornea and destroy the tissue in your eye socket, it’s a medical emergency. If you have symptoms of a corneal ulcer, seek immediate care. Corneal ulcers can cause blindness if not promptly treated.

What are the causes of a corneal ulcer?

Causes of corneal ulcers include:


  • Bacterial infections. Bacterial infections are the most common cause of corneal ulcers. These infections are common in contact lens wearers who don’t properly clean their contacts or wear them while sleeping. Pseudomonas aeruginosa, coagulase-negative staphylococcus and staphylococcus aureus are common bacterial causes.
  • Viral infections. Viruses that can flare up and cause corneal ulcers include cold sores (herpes simplex) and shingles (herpes zoster).
  • Fungal infections. These infections can happen if you have an injury to your cornea followed by an infection with plant or vegetable material. Aspergillus, Fusarium, Scedosporium apiospermum, phaeohyphpmycetes and candida species are common fungal causes.
  • Parasitic infections. Acanthamoeba is an amoeba found in air, fresh water and soil. An infection, Acanthamoeba keratitis, occurs when the organism gets into your eye. This can happen if you wear contact lenses and clean your lenses with tap water instead of disinfectant solution.

Other causes

  • Corneal abrasions. Bacteria can infect cuts, scrapes or scratches to your eye. Abrasions can happen from a fingernail scratch to your eye, a particle of dirt or other material that gets trapped or rubbed in your eye and other causes.
  • Corneal burns. Certain chemicals found at home or work can get into your eye and erode your cornea.
  • Severe dry eyes. This is a condition in which your tears (your eye’s “windshield washers”) can’t properly clean and lubricate your eyes. Without tears, particles remain on your eye and may scratch it and infection can set in.
  • Eyelid closure problems. Disorders that don’t allow your eyelids to close all the way can lead to dry eye conditions, which can lead to a corneal ulcer. Disorders include Bell’s palsy, Grave’s disease and other thyroid disorders. Other eyelid or eyelash problems that can lead to corneal ulcers include ingrown eyelashes (trichiasis), eyelid inflammation (blepharitis) and an in-turned eyelid (entropion).
  • Autoimmune diseases. Several autoimmune diseases can cause peripheral ulcerative keratitis (PUK), which leads to a corneal ulcer. Types of autoimmune diseases tied to PUK include rheumatoid arthritis, Wegener granulomatosis, relapsing polychondritis, polyarteritis nodosa, Churg-Strauss syndrome and microscopic polyangiitis.
  • Vitamin A deficiency. Lack of vitamin A causes the cornea to become dry. It also helps build new eye tissue. Most people in developed countries get plenty of vitamin A, but people with digestive problems or unusual diets can have low vitamin A. In the developing world, vitamin A deficiency is a major cause of childhood blindness.

Diagnosis and Tests

How is a corneal ulcer diagnosed?

Your eye care provider will:

  • Perform an examination with a slit lamp microscope. The slit lamp focuses a narrow “slit” of light onto the eye. A slit lamp exam is a normal part of an eye exam.
  • Your provider may apply a fluorescein dye to your eye. This yellow dye highlights any damage to your cornea.
  • Take a sample of the infected tissue. The results will show the type of infection and guide medication choice for treatment.

Management and Treatment

How is a corneal ulcer treated?

Corneal ulcers are treated with anti-infective medications or surgery if medications aren’t an option.

Medication choice is based on what’s causing the infection. Eye drops containing antibiotics (for bacterial infections), antifungals (for fungal infections) and antivirals (for viral infections) are the usual treatments. Your eye care provider may sometimes choose oral medication (taken by mouth) or an injection, given near your eye.

Your eye care provider may also prescribe oral medication to reduce pain. Steroid eye drops are sometimes given to reduce eye inflammation and swelling. Because steroid drops may worsen an infection, you should follow your provider’s recommendations about their use. Your eye care provider will discuss this and all available treatment options.

How long will I need to take medications?

You may need to take anti-infective medications frequently (every 1 to 2 hours) for several days. Your eye care provider will discuss how often to take your medications during your office visit.

How long does it take for a corneal ulcer to heal?

Most corneal ulcers heal in two or three weeks.

What can happen if a corneal ulcer is not treated?

Untreated corneal ulcers can lead to:

  • Scars on your cornea that may interfere with your vision.
  • Severe vision loss or blindness.
  • Astigmatism.
  • Cataracts or glaucoma.
  • Loss of your eye if the infection spreads (rare).

Is there any laser treatment?

After the infection is gone from your cornea, scars that limit vision are common. A laser treatment called phototherapeutic keratectomy (PTK) can improve some scars. If a scar isn’t too deep, your provider may be able to use the laser to burn the scar tissue away and improve vision.

When is corneal transplant surgery considered?

You may need a corneal transplant if:

  • Medications can’t treat your corneal ulcer.
  • The medications healed the corneal ulcer but left a scar that interferes with your vision and is too deep for laser treatment (PTK).

In either case, you’ll need a new cornea to restore your vision. The tissue for a corneal transplant comes from a person who has recently died. The tissue is tested to make sure it’s healthy before the old corneal tissue is removed and the new tissue is stitched in place in your eye.

What are the complications of a corneal transplant?

Complications include:

  • Rejection of the donor tissue.
  • Eye infection.
  • Swelling of the cornea.
  • Development of glaucoma or cataracts.


How can I reduce my risk of a corneal ulcer?

The best way to prevent a corneal ulcer is to see your eye care provider right away if you have an eye injury or think you have symptoms of a corneal ulcer.

Contact lens use is the highest risk factor for a corneal ulcer. With this in mind, some helpful tips for contact lens wearers include:

  • Always wash your hands before touching your eyes.
  • Properly clean and disinfect your contact lenses before and after wearing them.
  • Don’t sleep while wearing your contact lenses. Always take them out every night.
  • Don’t swim or shower in your contacts.
  • Don’t buy contacts from nonmedical sources.
  • Don’t wear your contacts if your eyes are irritated.
  • Clean and sterilize your contact lens case with the proper solutions.
  • Be aware of the increased risk of infection with extended wear lenses. Talk with your eye care provider or optician if you have questions.
  • Ask your eye care provider when to throw out and replace your contacts.
  • Always wear protective eyewear if you work or have hobbies that put you at risk for an eye injury.

Outlook / Prognosis

What can I expect if I have this condition?

A corneal ulcer is a serious eye condition that can cause vision loss. Your outcome depends on the cause and location of the corneal ulcer. The earlier you see your eye care provider, confirm the diagnosis and start treatment, the better your outcome.

Living With

When should I call my eye care provider?

Contact your eye care provider right if you:

  • Develop symptoms of a corneal ulcer.
  • Have a corneal ulcer and your symptoms worsen.
  • Develop severe eye pain, your pain or your vision is becoming worse.

Additional Common Questions

Why does wearing contact lenses increase the risk of a corneal ulcer?

Wearing contacts for long period blocks oxygen from reaching your eyes. Also, bacteria on the lens — transferred from your finger when inserting or from non-sterile cleaning solutions — can get trapped under your lens. These factors raise the risk of infection, which can lead to a corneal ulcer.

A contact lens wearer is about 10 times more likely to get a corneal ulcer than someone who doesn’t wear contacts. Someone who sleeps in contact lenses is about 100 times more likely to get an ulcer than someone who doesn’t wear contacts.

What’s the difference between a corneal abrasion and a corneal ulcer?

A corneal abrasion is a scrape or scratch on your cornea. These corneal injuries usually heal on their own

A corneal ulcer is an open sore on your cornea. Infections, dry eye and other conditions cause a corneal ulcer.

What’s the difference between a corneal ulcer and keratitis?

These eye conditions are closely related.

A corneal ulcer is an open wound — a loss of corneal tissue — that’s often the result of an eye infection.

Keratitis is a more general term for a group of disease processes that cause inflammation of your cornea. Eye infection, injury and wearing contact lenses too long — some of the same causes of corneal ulcer — also cause eye inflammation. Keratitis can lead to a corneal ulcer.

Both conditions can lead to vision loss.

A note from Cleveland Clinic

Corneal ulcers are a vision-threatening eye emergency. Even a minor eye injury can lead to a corneal ulcer. If you think you have symptoms of a corneal ulcer, contact your eye care provider right away. They will examine your eye, make the diagnosis and start treatment. If you wear contact lenses, make sure you know how to properly insert, clean and store them. Your eye care team can teach you proper techniques and answer all your other questions.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 03/08/2022.

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