Conjunctivitis is an inflammation of the mucosa on the backside of the animal's eyelids that attaches to the eyeball and thus forms a small pocket.
In the case of pinkeye, the conjunctiva (the area exposed when pulling down the eyelid) is invariably blood-shot, which is especially obvious when only one eye is affected. In severe cases, the conjunctiva bulges out from under the eyelid like a pink-red cushion. As a result, tear production increases markedly. The coat around the corner of the eye then becomes damp and forms a wet track descending towards the mouth. Mild cases of conjunctivitis may heal spontaneously. If the inflammation is persistent, a cloudy discharge from the eye may develop. Cases where the inflammation affects the cornea and causes the eye to appear milky and clouded are known as “cerato-conjunctivitis".
Bacterial infection is a common cause of conjunctivitis. One difference between dogs and cats is that viruses are rarely the cause an eye inflammation. Decreased tear production, extreme heat or cold, as well as some conditions of the eyeball itself may cause symptoms of conjunctivitis.
In mild cases treatment with anti-inflammatory eyedrops is sufficient. In more severe infections, and for animals who suffer from pinkeye repeatedly, oral antibiotics are necessary.
If symptoms do not disappear within 1-2 days, or appear to worsen, consult a veterinary clinic.