Conjunctivitis: Causes and Symptoms

Conjunctivitis is an inflammation of the mucous membranes (conjunctiva) that line the inner surface of the eyelids and the whites of the eyes. It may be triggered by either an infection or an allergic reaction.

Known as "pink eye" because the blood vessels in the whites of the eyes dilate and redden, conjunctivitis is highly contagious when caused by an infection. It is usually not serious, although it should be treated promptly to prevent possible complications and transmission to others. With proper treatment, conjunctivitis generally disappears within two or three weeks.

Causes

• Bacterial or viral infections are the most common causes of conjunctivitis.
• Allergies (to such things as pollen, cosmetics, and contact lens cleaning solution) are a possible cause.
• Air pollution or chemical irritants may lead to conjunctivitis.
• Cervical infections (chlamydia, genital herpes or gonorrhea) in a pregnant woman may result in potentially blinding conjunctivitis in her baby.
• A partially blocked tear duct is a possible cause.

To prevent conjunctivitis, try never to touch the eyes when, for example, handling contact lenses. Wash your hands often with soap and warm water. Change towels and pillowcases often. Do not share towels. Do not share eye makeup, and replace cosmetics every four to six months. Avoid substances that trigger eye irritation.

Symptoms

• Redness of the white of the eye
• Itching and a gritty sensation in the eye
• Oozing discharge from the eyes that may form dried crusts during sleep, which may bind the eyelids together
• Excessive tearing
• Swollen eyelids
• Aversion to bright lights (photophobia)

Call a doctor if conjunctivitis symptoms do not improve after three or four days of treatment, especially if fever, increased pain or changes in vision develop. In the case of bacterial conjunctivitis, prompt treatment will avert complications.

Last Updated: 1/15/2003
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