The whites of a dog’s eye may turn red if the eye is irritated either from environmental particles or as a result of internal disease processes.
These different causes often have distinct features that set them apart and could help you narrow down the possible causes.
Here are some of the most common reasons why the whites of your dog’s eyes may be turning red.
Allergies And Environmental Irritants
These cause an immediate reaction by immune components on the surface of the dog’s eye resulting in signs and symptoms like watering, itchiness, and the redness that you will see. Some of the most common of these irritants are smoke, dust, and pollen.
Glaucoma is a serious condition of the eye that causes increased intraocular pressure in the dog’s eye. This could cause irritation from within which triggers similar reactions as environmental irritants including redness and watering.
You may also notice signs of worsening vision in the dog. These include increased confusion, hesitancy to walk or run, and the dog bumping into obviously visible objects.
Foreign Bodies In The Eye
Another reason why your dog’s eye may be red and itchy is that they may have a foreign object either on the surface of the eye, under the eyelids, or penetrating the eyeball. This caused irritation and will usually affect only one eye in most cases.
The dog’s red eye could also be caused by eye infections. In addition to the redness of the white parts, the infections could cause inflammation of the surrounding tissues including the eyelids. This may give the dog red eyes that seem half closed.
Infections are also associated with discharge that may look a lot like pus or be clear and watery.
Dry Eye Syndrome
Dry Eye Syndrome is sometimes referred to as Keratoconjunctivitis sicca. The condition is caused by loss of the tear film that protects the surface of the eye. This results in exposure to and irritation by things like flowing air that would normally not cause irritation.
The loss of the film also exposes the dog’s eye to environmental particles like smoke and dust that cause the irritation and redness.