Red discoloration of an animal’s eye is mostly a sign of an inflammatory condition and infection. There are numerous diseases that require different treatments. Most common are:

Conjunctivitis, Keratitis, Cherry Eye, Glaucoma, Cataracts, Scleritis and Uveitis.

This is the most common eye disease of all domestic animals. It causes inflammation of the mucous membranes of the eye-is the most common eye disease of all domestic animals,” Purebred dogs and animals that suffer from allergies are most likely to conjunctivitis. The blood flow inside the eye increases and makes the eye appear red. In addition some swelling of the mucus membranes might be seen. This disease is caused mostly by viruses or bacteria, in some cases by parasites. Ticks can transmit several parasites resulting in conjunctivitis.

The discharge depends on the severity of the infection, it can be clear or contain mucus. The eye(s) will itch and first and foremost it is important to keep it clean, then treat it with medication your vet will prescribe.

The “Chronic superficial keratitis” occurs almost exclusively in German Shepherds, seldom in other breeds. This disease causes increased pigmentation on the eye and an increase in blood vessels. The animal might not experience a lot of pain but the disease needs to be treated because the animal’s vision will be impaired and can worsen over time.

Keratitis also occurs in chronic cases of keratoconjunctivitis sicca (KCS) that has it’s reason in not enough moisture in the tear film. Over time the cornea layer becomes infiltrated with blood vessels, discolored, and harder due to the irritation. Treatment with tear stimulants and anti-inflammatory eye drops normally work well. The discharge is a thick and ropy-like mucous.
In case keratitis is associated with eye ulcers surgical treatment might be needed.

Is an inflammation of the eyelid caused by dermatitis, sun damage, a fungal infection, a bacterial parasite, trauma, a metabolic problem, or an immune system problem.
Cherry eye commonly affects younger dogs. Cocker Spaniels, Pekinese, Bulldogs and Beagles are more prone to this infection. Cherry Eye can occur on one or both eyes.

Treatment varies depending on the cause of the inflammation. In some cases the prolapsed gland of the third eyelid needs to be surgically replaced.

Glaucoma needs to be treated immediately or it can lead to blindness. If you detect symptoms such as cloudy pupils, large pupils and redness, consider this as a real emergency, same as if your dog would have been hit by a car. Medical treatment must be started right away to preserve the dog’s vision and will consist of reduction of the pressure in the eye before blindness sets in.

Glaucoma can be triggered by yeast infection from the yeast bacteria. Some breeds are more prone to get this disease than others. A study reveiled that it is most common in breeds like Boston Terrier, Siberian Husky, Cocker Spaniel, Basset Hound, Chow Chow, Miniature Poodle and Wire Fox Terrier.

These are white opacities in the lenses of the eyes that impair vision or cause blindness. Mostly seen in young animals of certain breeds, such as the Poodle or the English Cocker Spaniel. Most cataracts are inherited but can also develop later and are caused by injuries, diabetes, poor nutriton (orphaned puppies placed on an artificial milk replacement diet), infections, toxins or radiation therapy. The cataract may develop rapidly over weeks, or slowly over years, in one or both eyes. Cataracts develop often after animals get older, mostly 8 years or more.
There is no treatment to clear the lens from a cataract. Surgically removal is necessary.

This is an inflammation of the white outer coat enclosing the eyeball, called the sclera. Scleritis mostly results from a parasitic disease, such as toxoplasmosis or lyme disease. It usually involves one eye only and may develop suddenly. Treatments include steroids, but when untreated, it can result in the loss of eyes.

Results in an overflow of tears, eyelid spasms, sensitivity to light and small pupils. Uveitis is an inflammaftion that is very common in domestic animals – and humans. Treatment is needed to prevent harm of vision. The cause for uveitis normally is an underlying parastic disease, such as toxoplasmosis.
(Read more about >> Toxoplasmosis)