What is pink eye (conjunctivitis)?

Conjunctivitis, often called "pink eye," is an inflammation (swelling) of the conjunctiva, the tissue that lines the inside surface of the eyelid and outer coating of the eye. This tissue helps keep the eyelid and eyeball moist. Pink eye is one of the most common eye infections in children and adults.

What causes pink eye (conjunctivitis)?

Pink eye can be caused by a virus, bacteria, irritating substances (shampoos, dirt, smoke, and especially pool chlorine), allergens (substances that cause allergies) or sexually transmitted infections. Pink eye caused by bacteria, viruses, and sexually transmitted infections can spread easily from person to person, but is not a serious health risk if diagnosed promptly.

What are the symptoms of pink eye (conjunctivitis)?

The symptoms of pink eye include the following:

  • Redness in the white of the eye or inner eyelid
  • Greater amount of tears
  • Thick yellow discharge that crusts over the eyelashes, especially after sleep (in conjunctivitis caused by bacteria)
  • Other discharge from your eye (green or white)
  • Itchy eyes (especially in pink eye caused by allergies)
  • Burning eyes (especially in pink eye caused by chemicals and irritants)
  • Blurred vision
  • Increased sensitivity to light

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