Dog Health by LowchensAustralia.com

Whenever hair rests around the eyes some amount of tear staining results from the hair wicking moisture from the eyes. But there are many other sources of tear stains. 
Tear staining can be traced to health and diet, as well as genetics. Most veterinarians agree that face staining results from excessive tearing. In this case, the damp face hair is a breeding ground for bacterial and yeast growth. The most common is "Red Yeast" which is usually associated with reddish-brown facial stains, and which may emit a moderate to noticeably strong odour. Tear ducts may become infected and result in excess tearing and noticeable staining.
Some doctors advise that the eye structure was the most probable source of the problem. If that is so, then genetics would likely play a role and explain why the problem is more pronounced in some pets of the same breed. If you are purchasing a puppy and you care concerned about the potential for tearing and staining, you should observe the mother and sire, and others in the direct lineage.
Eye duct surgical procedures to increase their tear capacity may help some pets; ask your veterinarian.
If bacterial and yeast infections are involved you need to take steps to mollify and eliminate their presence. Veterinarians can prescribe medication to treat bacterial and yeast infections. Your veterinarian or eye specialist veterinarians can determine if excessive tearing is the source of stains, and describe alternatives available.

Epiphora is the medical term for excessive tearing or watering of the eyes. It commonly causes staining of the fur under the eyes. There are many causes, but the most common are chronic irritation or inflammation of the eyes and an abnormality in the tear drainage system. A related problem is not truly epiphora, but appears to be so, and that's a blocked tear duct. Normally, tears leave the eye by going down a tear duct into the nasal passages, but if the duct is clogged up or blocked, the tears spill over the lower lid ... looking just like excessive tears.

Common causes of chronic irritation in dogs include infections, allergies and abnormalities of the eyelashes and eyelids. In cats, viral infection is common, which usually causes the eyes to appear mildly or moderately inflamed. 

If your dog or cat seems to be tearing excessively, have him or her checked by a veterinary ophthalmologist to determine whether treatment is needed. 

Abnormalities of the tear drainage system can be treated by flushing the system and applying medication, but sometimes surgery is required. Sometimes all you have to do is trim excessive hair from near the eye.

Excessive tears in themselves are not a danger to your pet, but it's important to make sure there isn't some reason causing the tears that needs attention. As you know from your own experience; things that cause your eye to tear are often very irritating and sometimes quite painful. Some breeds have tears that discolour their faces simply because of poor tear drainage, often because of the way the eye bulges out in some breeds such as Boston Terriers or Persian Cats. Or because of inadequate tear duct size in other breeds such as poodles and Maltese dogs. And, of course, this is more noticeable if you have a white dog or cat.

By the way, the trail of tears down the cheek appear as rust coloured stains because there's iron molecules in tears ... after the water part evaporates ... it leaves behind oxidized iron molecules.

There are eye drops and oral medications that either reduce tear flow, dilate tear ducts, or bind iron molecules available from your vet and in some pet stores, but there are potential problems. Ask your vet.

Cleaning the Eye 
It is important to clean your pet's eyes of any discharge before instilling medicine into them. Eyelids can be cleaned by applying a few drops of diluted baby shampoo (1 part shampoo to 20 parts of water) to a wet cotton ball or gauze square and massaging the eyelids gently with the eyes shut. Once all crusts and discharge have been removed, wash away the shampoo with one or more cotton balls or squares moistened with water only. 

If discharge has collected inside the lids or on the eye itself, begin removing it by slowly dripping sterile saline (found in the contact lens department of any pharmacy) onto the eye from above. Then, when the discharge has been rinsed to the corner of the eye, use a tissue or cotton ball to draw it out of the eye.

Medicating the Eye 
To apply eye drops to your pet's eye, lift the muzzle upward with one hand and drip the medication from above with the other. It is helpful to rest the heel of the hand that is holding the bottle on the animal's forehead so that the bottle does not inadvertently touch the animal's eye. Let the medicine drip from a height of at least 1 inch, taking care not to touch the tip of the bottle to the fur. 

Remember that only one or two drops are needed at any one treatment. If you are using more than one kind of medicated eye drop, space the treatments by at least 5 to 10 minutes rather than applying both medications to the eye at once, so that each medicine will get a chance to be absorbed. 

When applying ointment, be careful to use only a small amount because a long strand can be irritating. Apply it to the inner corner of the eye or to the white part of the eye, known as the sclera, and then gently rub the eyelid over the eye to distribute the medicine. It may be helpful to rest your hand on your pet's forehead to steady yourself as described above for eye drops. 

If you are using both eye drops and ointment, apply the eye drops first, spaced at 5 to 10 minute intervals if you are using more than one eye drop medication, and wait at least 5 to 10 minutes before applying the ointment. 

Conjunctivitis is an inflammation of the membrane that covers both the inner lining of the eyelid and the white of the eye. It may be caused by infections, allergies, inadequate tear production or irritation. Click here to learn more

Keratoconjunctivitis Sicca (DRY EYE) occurs when the tear glands do not produce enough tears. This results in recurrent or chronic conjunctivitis - persistently sore eyes - and, untreated, may eventually lead to blindness. Certain breeds, such as West Highland White Terriers, Cavalier King Charles and Cocker Spaniels, seem to be more prone to this problem, though any dog may be affected. Click here to learn more

Corneal Ulceration can occur when the shiny surface of the cornea is scratched or damaged.

Epiphora. If your dog's eye constantly 'weeps', or if the fur around it appears 'stained', the normal tear flow may be blocked.

Cataracts & Glaucoma. Dogs, just like humans, can have these serious eye diseases. Cataracts cloud the lens inside the eye and are the most common cause of canine blindness. A hereditary condition in some breeds, early examination by your veterinary surgeon is important, as such animals should not be bred. Glaucoma stems from too much pressure being exerted upon the eye's interior as a result of a decrease in the amount of fluid draining from it.

Pannus (Chronic Superficial Keratitis)
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