When a vigorous scratch fails to relieve an itch, your dog will keep scratching. Incessant scratching, often combined with licking and biting at the itchy spot until the skin breaks and the fur wears away, suggests the presence of skin disease. As uncomfortable as most skin conditions are for dogs, vets can usually diagnose and treat them easily so they seldom become life-threatening. An exception is melanoma. Even though the first sign of this malignant cancer might resemble a harmless mole, immediate medical intervention is an urgent priority.
Most Common: Flea Allergy Dermatitis
All dogs are flea magnets, but those with allergic reactions to flea saliva suffer from North America's most common canine skin disease, flea allergy dermatitis. Onset is most likely in summer, when outdoor flea populations are highest. If the parasites become established indoors, they can torture dogs year-round. When skin becomes inflamed and intensely itchy at flea bite sites, dogs respond by licking, scratching and biting, creating conditions ripe for secondary infections. Patchy hair loss, especially on the rump and upper tail area, is common. Treatment protocols involve eliminating fleas on the dog and inside the home, clearing up skin infections and taking measures to prevent re-infestation.
Most Deadly: Melanoma
The first visible sign of canine melanoma often resembles a mole, usually inside a dog's mouth or on a toe. By the time the disease reaches that stage, the cancer has often already spread. The Veterinary Cancer Care Center advises aggressive treatment to save the dog's life. Male dogs and certain breeds, including Scotties, cocker spaniels, Gordon setters, chow chows and golden retrievers, contract melanoma more frequently than others. If a black, pink or white swelling in your dog's mouth is accompanied by drooling, weight loss and pain, or if you notice he has a swollen toe and has started limping, get him to the vet as soon as possible. Treatments for melanoma include surgery, chemotherapy and radiation.
Food Allergies and Skin Disease
Symptoms of food allergies may show up on a dog's skin. The offending substances are typically proteins in beef, chicken, eggs, dairy or soy products, but dogs with food sensitivities often have other allergies, such as to mold or parasites. If so, the immune system will target these allergens for separate attacks, further inflaming the skin. To relieve symptoms, all existing allergies must be treated simultaneously. Michigan State University's Veterinary Teaching Hospital says collies, German shepherds, golden retrievers, Labrador retrievers, springer spaniels, cocker spaniels and Shar-Pei breeds appear to suffer from food allergies more than others. Symptoms include patchy hair loss from scratching, usually in conjunction with gastrointestinal problems such as vomiting and diarrhea. Standard veterinary procedure for diagnosing food allergies involves a 12-week elimination diet to pinpoint the allergen; treatment proceeds from there.
The Misery of Mange
Mites, microscopic parasites related to ticks and spiders, live on the skin and in the hair follicles of many warm-blooded creatures, including people. Two varieties of thousands of existing species cause skin disease in dogs. Sarcoptic mange mites burrow into the skin, causing intolerable itchiness. By attempting to relieve it, dogs scratch themselves bloody, resulting in sores, scabs and hair loss, most often on ears, legs and faces. Also known as scabies, sarcoptic mange is contagious among dogs and can be passed to humans. Though symptoms of demodectic mange are similar, sarcoptic mange is often accompanied by a foul odor. It can indicate underlying health threats such as immune system disorders. However, it doesn't pass as easily among dogs and doesn't jump the species barrier to humans. Depending upon the type and severity, vets treat mange with topical, oral and injection medications.