Conjunctivitis is the term used to describe swelling (inflammation) of the conjunctiva — the thin, filmy membrane that covers the inside of your eyelids and the white part of your eye (sclera). Conjunctivitis is often called “red” or “pink” eye.

The conjunctiva, which contains tiny blood vessels, produces mucus to keep the surface of your eye moist and protected. When the conjunctiva becomes irritated or swollen, the blood vessels become larger and more prominent, making your eye appear red. Conjunctivitis may occur in one or both eyes.

What are the symptoms of conjunctivitis?
Symptoms of conjunctivitis include:

Viral infection
Viral infection is the most common cause of conjunctivitis. This same virus produces the familiar red and watery eyes, sore throat and runny nose of the common cold. Symptoms of conjunctivitis can last from one to two weeks and then will disappear on their own. Discomfort, however, can be minimized with cool compresses applied to the eyes.

Bacterial infections, such as Staphylococcus or Streptococcus, cause a red eye that has a lot of pus. Some bacterial infections, however, may be ongoing infections that produce little or no discharge except for some mild crusting of the eyelashes in the morning. Antibiotic eyedrops are typically used to treat bacterial conjunctivitis.

Conjunctivitis, whether bacterial or viral, can be quite contagious if it is infectious. Practicing good hygiene can help prevent the spread of conjunctivitis if you are infected. You should:

Allergic conjunctivitis
Allergic conjunctivitis in not infectious or contagious. It occurs when the body is exposed to something that causes an allergic reaction, such as pollen or pet dander, and is often seasonal. Symptoms include redness, itching, burning, tearing, enlarged vessels in the sclera (white part of the eye) and puffy eyelids. Treatment often includes applying cool compresses to the eyes and taking antihistamines.

Generally, conjunctivitis is easily treated. However, if symptoms continue for an extended period of time after treatment, you should have your eyes examined by your ophthalmologist (Eye M.D), as these symptoms may indicate a more serious eye problem. There are several eye diseases that cause red eye, some of which can lead to blindness unless diagnosed and treated.

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