(HealthDay News) -- Conjunctivitis, commonly called pinkeye, is an infection or inflammation of the membrane that lines the eyelids.

The cause is most often a virus, but a bacterial infection, allergies, exposure to chemicals or use of contact lenses also may be triggers.

Pinkeye is not only uncomfortable, but usually very contagious.

The ADAM Encyclopedia says these are common symptoms of pinkeye:

  • Red eyes.
  • Crusty eyelids that develop overnight.
  • Eyes that itch and tear up more than usual.
  • A feeling of grit in the eyes.
  • Blurred vision.
  • Sensitivity to light.