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Quick Facts

Eye Redness


The Manual's Editorial Staff

Last full review/revision May 2021| Content last modified May 2021
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Sometimes the white part of your eye turns red. Usually this happens because small blood vessels on the surface of your eye swell with extra blood. Sometimes it's because some of these small blood vessels break open and bleed.

What causes red eyes?

The most common causes are:

Many painful eye problems also make your eye red. These problems include:

  • Scratches on your cornea (the clear layer at the front of your eye)

  • Having something in your eye (like a bug or a grain of sand)

  • Glaucoma Glaucoma read more (high pressure inside your eye)

However, with these problems, you're most likely to want to see the doctor because of your eye pain.

When should I see a doctor?

See a doctor right away if you have red eyes and any of these warning signs:

  • Sudden, intense eye pain and throwing up

  • A rash on your face, especially if it's around your eyes or on the tip of your nose

  • Not able to see as clearly or sharply as usual

  • An open sore on the front of your eye

If your eyes are red but you don't have any of these warning signs, you can wait a couple of days to see a doctor. You can usually see a regular doctor instead of an eye doctor.

What will happen at my doctor visit?

Doctors will ask about your symptoms and medical history. They’ll examine you and check your head and neck for signs of an infection or allergy. Doctors may:

  • Check your vision with an eye chart

  • Put some liquid drops in your eye (you may have a burning feeling that lasts a few seconds)

  • Look into your eye using a special magnifying light (the light is very bright)

  • Measure the pressure in your eye (there are different ways to do this, but none of them hurt)

If doctors think there's something in your eye, they may briefly turn your eyelids inside out to look more closely in your eye. This may feel a little strange or uncomfortable, but it doesn't hurt. You may have blood tests or x-rays if doctors think you may have an infection behind your eyeball.

How do doctors treat red eyes?

Doctors treat what's causing you to have red eyes, such as an allergy or infection.

  • Eye redness usually clears up on its own after doctors treat the cause

  • If your eye is itchy, place a cool washcloth over it or use artificial tears (eye drops that act like real tears to wet the eye)

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version


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