Tear stains are caused by excessive tearing and appear as reddish strips on the hair beneath a dog's eyes. Tear stains are unsightly, and can cause irritation and infection when left untreated. If your dog has recurring tear stains, your veterinarian can investigate the cause of the stains and rule out any potential health concerns.
Appearance of Tear Stains
According to Healthy Pets, tear stains, otherwise known as epiphora, are caused by excessive production of tears and are most common in the Lhasa apso, Shih Tzu, cocker spaniel and pug, though the stains will appear darker on any dog with a light-colored coat, such as the Maltese, American Eskimo, West Highland white terrier, bichon frise and poodle. Porphyrin, a byproduct of red blood cell breakdown, contains iron and can be shed through a dog's saliva, tears or urine. The iron causes the reddish stain, which will become darker if exposed to sunlight.
Causes of Tear Stains
Some dogs may develop more tear stains than others due to higher tear production, while others will develop the reddish streaks due to a medical issue. Stains could be due to ingrown eyelashes, eye infections, tear duct and gland abnormalities, medications and ear infections. Entropion, or inverted eyelid, may cause tear stains, as can glaucoma or other eye diseases. Other causes include ear infections, medications, allergies, secondhand smoke, poor diet, stress and teething in puppies. Dogs with brachycephalic syndrome are more likely to develop an abundance of tear stains due to the conformation of their skull, according to Healthy Pets.
Your dog's veterinarian will first determine the cause of the epiphora, if possible. The veterinarian will perform an ocular examination to check for abnormalities or inflammation in the tear ducts. If the lacrimal, or tear duct, is blocked by hair or debris, the veterinarian can flush it while your dog is under anesthesia. Flushing the duct may help to widen it, particularly if the dog's epiphora is caused by allergies or infections. According to VCA Animal Hospitals, the underlying cause for epiphora may be unclear, and your dog may continue to develop tear stains throughout his life.
Tears can cause matting of the hair beneath the eye, which can in turn cause skin irritation and infection. Yeast infections can develop when tear stains are left untreated; these will turn brown and produce a noticeable odor. Your dog's face should be cleaned twice daily with warm water and a cotton ball. A small amount of coconut oil smeared in the track of the tears will prevent skin irritation. A groomer can shave the hair in the corner of the dog's eyes if he is developing mats or a crust near his eyes. The addition of parsley flakes to your dog's diet may lessen his tear production and the stains that result, according to VCA Animal Hospitals.