This term describes a group of diseases that cause swelling, itching, burning, and redness of the conjunctiva, the protective membrane that lines the eyelids and covers exposed areas of the sclera, or white of the eye. Conjunctivitis can spread from one person to another and affects millions of Americans at any given time.

Conjunctivitis Causes

  • Allergy
  • Bacterial or viral infection
  • Contact lens product
  • Environmental irritants
  • Eye drops
  • Eye ointments

When it starts, conjunctivitis is usually painless and does not affect vision. The infection will clear in most cases without seeing a doctor, but for some forms of conjunctivitis, you might need treatment. If treatment is delayed, the infection may worsen and cause corneal inflammation and a loss of vision.