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