Pinkeye is conjunctivitis and most people associate it with eye infections in humans. It also occurs in dogs and, in fact, is one of the most common eye ailments that occur in canines. It is an inflammation of the conjunctival membrane. The latter is a membrane that covers the back of the eyelid and the surface of the eye up to the cornea. There are a number of different things that can cause conjunctivitis.
The classic symptom of conjunctivitis is a red eye with discharge. It can occur in one or both eyes. The discharge can be clear (serous), mucus-like (mucoid), or pus-like (purulent). If it occurs in only one eye it is most likely caused by an irritant while both eyes is more likely to indicate disease. Conjunctivitis is contagious and can pass not only from dog to dog but also from human to dog or vice versa. It is very important that everyone in the household wash their hands after handling an infected individual regardless of species. If one pet in the house catches conjunctivitis, it can be safely assumed that all the other animals in the house will contract it and also need treatment.
Treat the symptoms with artificial tears to try to wash any irritants out of the eye. If it is caused by disease, antibiotic eye drops may be required. Because different diseases are treated with different types of antibiotics and some issues preclude the use of steroids while others require it, it is important to consult your veterinarian. A damp, soft, clean cloth can be used to wipe around the eyes and remove any discharge or crustiness.
The type of discharge can help determine the cause of the inflammation. Serous (clear) discharge often accompanies slightly swollen, pink eyes. It is usually indicative of the presence of an irritant such as dust, wind, cold weather or an allergen. Allergic conjunctivitis often produces itchy eyes that may lead to the animal trying to scratch them. This can lead to a more serious injury such as a scratched lens. While getting the allergy under control the dog may need to wear an Elizabethan cone to prevent scratching.
Irritation of the mucus glands in the eye can lead to the formation of a bumpy surface on the eye which produces a mucoid discharge. It can usually be treated with antibiotics but may require surgery if it continues to reoccur.
A pus discharge (purulent) is usually indicative of a bacterial infection such as Staphylococcus or Streptococcus. The eye often has crustiness around the lids where pus has leaked and dried. It can be quite serious and should definitely be seen by a vet.
Neonatal conjunctivitis occurs in newborn puppies whose eyes have not yet opened. Pus may be seen leaking out of the sealed eyelids and they often look puffy due to the trapped fluid on the eye. It is very important that puppies with this condition see a veterinarian immediately. Left untreated it can result in corneal damage or blindness. It is caused by bacteria that have access to the eye during birth or shortly thereafter.
Keratoconjunctivitis sicca (dry eye) is a condition where the body does not produce sufficient tears to keep the eye moist. Some breeds, such as the bulldog, West Highland white terrier, cocker spaniel, and Lhasa Apso, are more likely to suffer from dry eye. It is treated by moistening the eye with artificial tears. Left untreated it can cause blindness. Other congenital and genetic diseases that can cause conjunctivitis include distichiasis (extra eyelashes that may irritate the eye by rubbing against it), entropion (the eyelid rolls inward, so that lashes rub against the cornea), and ectropion (the eyelid hangs away from the eye exposing it to more debris in the air. In cases where the eyelashes rub against the eye, the constant irritation can lead to corneal damage if left untreated. In the case of ectropion care must be taken to avoid irritants getting into the eye. Some of these conditions may require surgical correction.
Conjunctivitis can be caused by many things include airborne irritants, allergies, disease and infection. It can also be the result of a congenital or genetic defect. In its simplest form it is treated with damp cloths and rinsing while more complex forms may require antibiotics or even surgery. The risk of permanent damage to vision exists if the problem is left untreated and does not clear up on its own. Therefore, you should always consult your veterinarian if a quick rinse of the eye does not produce an improvement.