Tear stains are quite common in small dogs with a light coat colour. Photo of Shih Tzu by Frank Pierson.
Dog tear stains do not look nice, which makes many dog owners try to get rid of the problem or, at least, to minimize it.

What are tear stains, and what dogs are prone to them?

The tear stains problem is very common in small dogs with a light coat colour, such as Terriers, Maltese dogs, Bichons, Shih-tzus, Poodles, Pomeranians, etc. These breeds have a special structure of the eyeball. Cats often suffer from tear stains too, especially Persians.
Tear stains change the colour of the hair under the eyes. The hair can get a brown or pink hue, and sometimes it is covered with sticky brown secretions. The latter has essentially the same nature as the secretion of the human eye in the morning. The pinkish-brown hue is caused by bacteria and yeast.

What causes tear stains?

Veterinarians say the cause of tear stains - excessive tearing - can be a result of several different factors such as tearing from irritation or discomfort, tear ducts contamination, inversion of eyelashes or eyelids, poor eyelid structure, and so on. Specialists often come across various anomalies such as an additional number of lashes or too thick eyelashes in the corners of the eyes. These conditions require medical and, sometimes, surgical correction. An allergy or eye pollution can also be the factors causing excessive tearing. For example, there is a known story about a dog that suffered from tear stains while its owner was an avid smoker. When the dog got to a new owner, the problem was gone within 18 months.
In most cases, however, tear stains are a cosmetic problem rather than a medical one. It is caused by improper care of the dog's coat. Matted long hair, especially wet, creates a perfect environment for skin infections and bacteria.

How to get rid of tear stains and prevent them?

First of all, you should keep the dog's skin and hair clean, especially under the eyes. Every day clean it with a damp cloth to remove contamination. Do not use cleaning chemicals such as mild soap because the toxic substance can get into the eye and irritate it. In some cases, you can use special eye drops prescribed by your vet.
If your dog has bushy eyebrows, it is strongly recommended that you have the hair around the eyes cut, especially in the corners of the eyes. This will help prevent excessive secretion. The trimming procedure requires skills and caution; if you've never done it before, let a groomer or a vet do this. By the way, some groomers recommend powdering the area under the eyes with baby powder. The others suggest boric acid: they rub it into the coat under the eye carefully. The substance fills the hair follicles, preventing tear secretion.
If you need to clean the fur from dried secretions, you can carefully brush the area with a thick brush. In severe cases, you may even have to cut off the dried hair. Again, this had better be done by a professional groomer or veterinarian to avoid accidental injury.
If your dog is prone to tear staining, you have to give it proper care every day. Moreover, the eyes should be checked by a veterinarian every once in a while. You may want to consult your vet about preventing eye infections. Lastly, do not allow your dog to stick its head out of the window during a car ride. If your dog loves that, use special sunglasses for dogs.