Conjunctivitis is an inflammation of the conjunctiva, the thin, transparent layer that lines the inner eyelid and covers the white part of the eye.

The three main types of conjunctivitis are infectious, allergic and chemical. The infectious type, commonly called "pink eye" is caused by a contagious virus or bacteria. Your body's allergies to pollen, cosmetics, animals or fabrics often bring on allergic conjunctivitis. And, irritants like air pollution, noxious fumes and chlorine in swimming pools may produce the chemical form.

Common symptoms of conjunctivitis are red watery eyes, inflamed inner eyelids, blurred vision, a scratchy feeling in the eyes and, sometimes, a pus-like or watery discharge. Conjunctivitis can sometimes develop into something that can harm vision so you should see your optometrist promptly for diagnosis and treatment.

A good way to treat allergic or chemical conjunctivitis is to avoid the cause. If that does not work, prescription or over-the-counter eye drops may relieve discomfort. Infectious conjunctivitis, caused by bacteria, can be treated with antibiotic eye drops. Other forms, caused by viruses, cannot be treated with antibiotics. They must be fought off by your body's immune system.

To control the spread of infectious conjunctivitis, you should keep your hands away from your eyes, thoroughly wash your hands before applying eye medications and do not share towels, washcloths, cosmetics or eye drops with others.

http://www.eye-care.org.uk