Leading Cause of Cold Sores on Dogs

Bad breath in your canine buddy may be symptomatic of disease.
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There is no alarm clock equal to the waking powers of a warm huff of odorous dog breath. A nasty smell coming from Barney's mouth can speak of something serious, so consider it a wake-up call. A strong odor often accompanies cold sores in and around your dog's mouth, but cold sores are not always isolated to Barney's mouth. They may occur in other areas of his body, causes vary.

The Cold Sore

The term cold sore is a generalized term for ulcerated lesions that result from several different causes. Similar to human reactions, canine skin can overreact to allergens and irritants, or the presence of a virus, and become red and inflamed. These lesions may occur in the mouth and may be indicative of stomatitis or may on a dog's wrist, indicative of a granuloma.

Acral Lick Granulomas

Frequently, dogs may develop a cold-sore type of wound on the wrist area called a granuloma. This is defined as toughened and raised tissue that occurs when dogs become focused on and lick the same spot repeatedly. A granuloma may result from an ingrown hair, from mites or from infection, but may also be caused by anxiety and boredom. Treatment varies depending upon the source of the granuloma.


Stomatitis or "sore mouth" can cause lesions located in and around a dog's mouth. Stomatitis is most commonly present due to periodontal disease and can also be caused by lacerations or burns to the dog's mouth. It is accompanied by drooling, bad breath and a inability or unwillingness to eat. Stomatitis can also have systemic causes such as kidney disease and hypothyroidism. Trench mouth, also known as St. Vincent's stomatitis, is the result of a bacterial presence, and thrush, a yeast stomatitis is normally caused by the prescription and ingestion of broad-spectrum antibiotics. All stomatitis is exceptionally painful and requires immediate treatment.

Proper Diagnosis and Treatment

There is no one more qualified to diagnose the cause of a cold sore or lesion than Barney's veterinarian. Treatment may include ointments, steroids, antibiotics and dental care, and are all administered under the careful eye of a medical professional. Barney can't take himself to the walk-in if something isn't right. He relies solely upon you, his best friend, to make sure he gets the urgent and ongoing health care he needs to live a long and happy life.