Also called conjunctivitis. Redness or irritation of the conjunctivae, the membranes on the inner part of the eyelids and the membranes covering the whites of the eyes. These membranes react to a wide range of bacteria, viruses, allergy-provoking agents, irritants and toxic agents. Viral and bacterial forms of conjunctivitis are common in childhood.

The leading cause of a red eye is virus infection. Viral pink eye is usually associated with more of a watery discharge, not green or yellow in color, and is frequently associated with viral cold-like symptoms. The eyelids may be swollen. Sometimes looking at bright lights is painful. While viral pink eye, may not require an antibiotic, the doctor should see the child, as occasionally this form of pink eye can be associated with infection of the cornea, (the clear portion of the front of the eyeball). This infection must be correctly detected and treated. Viral pink eye is highly contagious.

The bacteria that most commonly cause pink eye are staphylococcus, pneumococcus, and streptococcus. Symptoms include eye pain, swelling, redness, and a moderate to large amount of discharge, usually yellow or greenish in color. The discharge commonly accumulates after sleep. The eyelids may be stuck together requiring a warm wash cloth applied to the eyes to remove the discharge. This bacterial pink eye responds to repeated warm wash cloths applied to the eyes and antibiotic eye drops or ointment.

Chlamydia is a form a bacterial that is an uncommon form of pink eye in the U.S., but is very common in Africa and the Middle Eastern countries. It can cause pink eye in adults and neonates. It is a cause of pink eye in adolescents and adults that can be sexually transmitted. Chlamydia pink eye is typically treated with tetracycline (except in children less than eight years old, because of possible teeth discoloration) or erythromycin.

Redness in the white of the eye.
Gray or yellow drainage from the eye. This drainage may cause the eyelashes to stick together.
Mild pain.
Swelling of the upper eyelid, which may make the lid appear to droop (pseudoptosis).

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