Conjunctivitis In Dogs

My 5 year old labrador has had a red eye for several months and a friend suggested it might be conjunctivitis. Have you any advice about this? (Tony Crane - New York)

This does indeed sound like your dog may have a case of conjunctivitis but in all cases of concern for your pet's health a visit to the vet should be your top priority.

Conjunctivitis is an inflammation or infection of the conjunctiva, which is the tissue lining the eyelids and attaching to the eyeball near the cornea. This is the most common ailment affecting the eye of the dog, and can be caused by allergies or infections. Both allergies and infections cause a severe red appearance of the conjunctiva. This is caused by fluid build-up and an increase in the size and number of blood vessels within the tissue. Either allergies or infections cause the eye to discharge. The consistency of this discharge often reveals the cause.

Infections caused by bacteria or fungus typically create a thick yellow or greenish discharge, and the eyelids may actually stick together when held shut. Allergies will generally cause a clear discharge. The condition is usually treated with eye drops or ointments, and possibly anti-inflammatory drugs in the case of extreme allergy.