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Quick Facts

Allergic Conjunctivitis


The Manual's Editorial Staff

Last full review/revision May 2020| Content last modified May 2020
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The conjunctiva is the clear, thin layer that covers the white of your eye and the inside of your eyelids. Conjunctivitis is inflammation (swelling and irritation) of your conjunctiva.

What is allergic conjunctivitis?

Allergic conjunctivitis is a reaction in your conjunctiva caused by something you're allergic to, such as pollen, mold, or dust. Your eye gets swollen, red, and itchy.

Allergic conjunctivitis can be caused by:

  • Seasonal allergies to things like mold, tree, weed, or grass pollen (you usually have symptoms in the spring or fall)

  • Year-round allergies to things like dust, animal dander, or feathers (you have symptoms year-round)

There are other causes of conjunctivitis. For example, infectious conjunctivitis is caused by a viral or bacterial infection. Also, a speck of dirt, contact lens, or makeup can irritate the conjunctiva and cause conjunctivitis without there being an allergic reaction or infection.

Parts of the Eye

Parts of the Eye

What are the symptoms of allergic conjunctivitis?

You’ll have:

  • Itching and burning in both eyes

  • Red eyes and your eyeballs may look puffy

  • Watery eyes

  • Itchy, runny nose

You won't have any problems seeing.

How can doctors tell if I have allergic conjunctivitis?

Doctors can tell based on your symptoms. Usually, no tests are needed.

How do doctors treat allergic conjunctivitis?

Doctors will tell you to:

  • Use anti-allergy eye drops

  • Avoid things you're allergic to

  • Use artificial tears (eye drops that act like real tears to wet the eye)

  • Sometimes, use corticosteroid eye drops if symptoms are severe

If you also have other allergic symptoms, such as runny nose, sneezing, or itching, doctors may have you take an antihistamine by mouth.

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