Nasal depigmentation, also called Dudley nose, is a syndrome of unknown cause that may be a form of vitiligo. A nose that is solid black at birth gradually fades to a chocolate brown, or in the case of complete depigmentation, to pinkish white. Some dogs experience a remission in which the nose spontaneously becomes darker. Depigmentation primarily affects the skin of the nose where hair is absent. It tends to occur in Afghan Hounds, Samoyeds, white German Shepherd Dogs, Doberman Pinschers, Irish Setters, Pointers, and Poodles.
Snow noseisa separate but common condition in which dark pigment on the nose fades during the winter months and darkens again in spring and summer. Complete depigmentation does not occur. Snow nose is seen in Siberian Huskies, Golden Retrievers, Labrador Retrievers, Bernese Mountain Dogs, and other breeds.
Inflammatory bowel disease (IBD) occurs when a dog’s stomach and/or intestine becomes home to an unusually high number of inflammatory cells. These cells cause changes in the lining of the digestive tract, which inhibit the normal absorption and passage of food.
It is important to note that although some of the symptoms may be similar, IBD is not the same as irritable bowel syndrome, which is caused by psychological stress rather than a physiological abnormality.
Treatment:Lack of pigment on the nose is primarily a cosmetic problem and is considered to be a conformation fault in the show ring. A number of home remedies have been advocated, but their success is questionable. Sunscreen, as described for nasal solar dermatitis, helps prevent ultraviolet injury to dogs who lack pigment.
Plastic Dish Nasal Dermatitis
This is a localized form of depigmentation that affects the nose and lips. It is caused by eating out of plastic and rubber dishes that contain the chemical p-benzylhydroquinone. This chemical is absorbed through the skin and inhibits the synthesis of melanin, the substance that produces dark pigment in the skin. The involved skin may also become irritated and inflamed.
Treatment:The problem can be corrected by switching to glass, ceramic, or stainless steel bowls for all the dog’s food and water.
Treatment:Prevent further exposure by keeping your dog indoors as much as possible when the sunlight is the most intense-between 9 a.m. and 3 p.m. Letting the dog out on cloudy days does not address the problem, because ultraviolet rays penetrate clouds. Sunscreens are of some aid in protecting dogs who spend time outdoors. Use products containing an SPF greater than 15. Apply the sunscreen 30 to 60 minutes before exposure and again later in the day.
Treat an irritated nose with a skin preparation such as Cortaid that contains 0.5 to 1.0 percent hydrocortisone.