Conjunctivitis is the term used to describe inflammation of the conjunctiva: the thin, filmy membrane that covers the inside of your eyelids and the white part of your eye (the sclera). It is most commonly referred to as “red” or “pink” eye and can be caused by either a viral or bacterial infection, allergies or environmental irritants.

Symptoms of conjunctivitis include:

• Inflammation of the eye
• Increased tearing
• Soreness of the eye
• Foreign body sensation
• Itchiness of the eye
• Hazy or blurred vision due to mucous or pus
• Excess mucous (pus)
• Crusting of the eyelashes in the morning

Varieties

Viral conjunctivitis is much more common than the bacterial kind. It may last several weeks and is frequently accompanied by a respiratory infection (or cold). Antibiotic drops or ointments usually do not help, but symptomatic treatment such as cold compresses or over-the-counter decongestant eyedrops can be used while the infection runs its course.

Bacterial conjunctivitis is less common and characterized by considerable amounts of pus. Some bacterial infections are more chronic, however, and may produce little or no discharge except for some mild crusting of the eyelashes in the morning. Bacterial conjunctivitis can be treated with a variety of antibiotic eyedrops or ointments. These treatments usually cure the infection in a day or two.

Another kind of conjunctivitis is caused by allergies and often occurs in spring and fall. Itchy eyes are common with this variety, but can be treated with eyedrops. It is important, however, to not use medications that contain steroids unless prescribed by an ophthalmologist (Eye M.D.). Names of steroids usually end in “-one” or “-dex.”

Regardless of the cause, conjunctivitis should not cause a disruption in vision. More serious conditions, such as damage to the cornea, very severe glaucoma or inflammation inside the eye can also cause the conjunctiva to become inflamed and pink. If your case of “pink eye” affects your vision or you experience eye pain, you should see an ophthalmologist.

Prevention

Conjunctivitis can be very contagious. Practicing good hygiene can help prevent the spread of conjunctivitis if you are infected. You should:

• Avoid re-using handkerchiefs and towels to wipe your face and eyes;
  
• Not share towels, pillowcases or makeup;
  
• Wash your hands frequently;
• Keep your hands away from your eyes;
• Replace your eye cosmetics regularly;
• Properly clean your contact lenses;
• Stay out of swimming pools and consider staying home from school or work.

Last reviewed and updated in January 2009,
by the American Academy of Ophthalmology.