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DogCatEye

Conjunctivitis and red eye

Redness, discharge, squinting or rubbing may look like conjunctivitis, but ulcers, glaucoma and other painful disease can appear similar.

Veterinary assessment needed

Go to a clinic immediately if

  • The eye is cloudy, bulging, very painful, held closed, injured or vision changed suddenly
Contact a veterinary clinic

Possible signs

  • Redness, discharge, squinting, rubbing, swelling or a visible third eyelid
  • Discharge may be clear, mucoid or purulent and may affect one or both eyes

Contact a veterinarian today if

  • Squinting, pain, light sensitivity or corneal cloudiness needs assessment today

What it is

The conjunctiva lines the eye and eyelids. Allergy, infection, a foreign body, eyelid disease or inadequate tears can inflame it.

What to expect at the veterinarian

The veterinarian will assess the cornea, eye pressure, tear production and eyelids and may use fluorescein stain. Treatment depends on the cause.

Sources

Updated: 26 Oct 2026