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Consider any sources of severe itching. Research allergies for your specific breed of dog. Know when to take your dog to the vet. Understand what the vet will ask you. Be prepared for further testing. Learn common treatments.
Some potential causes of itching in dogs include the following:  Parasites, including lice, mites and fleas. Bacterial and yeast infections. These only occur when the skin is damaged or made vulnerable by some underlying disease or allergy. Food allergies. Environmental allergies. Hypersensitivity to tick or insect bites.  Less common causes include autoimmune diseases, endocrine diseases, certain cancers and others. While any dog breed can be allergic to something, certain breeds are prone to specific types of allergies. Do your research about what allergies or health conditions may be more likely with your dog's breed. This may give you a clue about what's bothering your pet. For example, if you have a cocker spaniel, you may learn that he is likely to get food allergies at some point in his life. You'll most likely notice itching on his ears and feet if he does have a food allergy. If you've practiced good flea control and give your dog a thorough bath, but he has been itching for more than seven days, your dog needs to see a vet. You should also take him to the vet if the scratching is so severe that you cannot distract him from scratching, or it stops it from eating or sleeping. Itchy skin in a dog may be a symptom of any number of health problems. This means that diagnosing and treating your dog's specific problem requires a step-wise approach. This will rule out causes of itching starting with the most common and progressing to rarer potential causes. Generally, veterinarians start examining an itchy dog by getting a thorough history and doing a physical examination. To help your veterinarian get an accurate picture of your dog's condition, consider writing out a history before the visit so that you don't forget to mention any critical facts. Some important facts to share include the following:  How long the dog has lived with you. Where you got the dog. How long the dog has been itchy and whether the problem has improved, gotten worse, remained constant or tended to wax and wane. Where on the body the dog seems to be itchy. The dog's current and past diets and any treats, table food or other food you give the pet. Where the dog spends its time (in the house, in the yard, roaming the woods, swimming in pools or natural bodies of water, etc.) Contact the dog has with other animals, including other household pets, wild animals in the yard or the woods and other dogs at the kennel, the groomer, the dog park or other places. Whether or not other pets or people in the household are itchy. Whether or not the dog has had problems with itching in the past. Whether or not the itching seems to be seasonal. The dog's medications, including flea and heartworm preventatives, prescription medications, topical ointments and shampoos, over-the-counter drugs and supplements. Any symptoms other than itching. Any steps, including bathing, supplements, diet, drugs, topical therapy, clipping and others, you have taken to try to control the itching and the dog's response to these interventions. The vet may recommend further tests, such as a microscopic examination of some plucked hairs, skin scrapings, ear swabs, blood tests or others to rule out the most likely causes of your dog's itching based on the pet's symptoms. These tests will help the veterinarian decide on a plan for treating your dog's skin issues. While some vets discourage it, other vets will recommend allergy testing for your dog. Testing is very expensive and may not be accurate since the tests were initially designed for humans. For this reason, elimination diets are usually used to determine allergies. Treatment depends on the severity of the symptoms and the cause or suspected cause of the itching. Common treatments include anti-parasitic medications, regular bathing with medicated shampoos, antibiotics, oral or topical steroids, immunosuppressive drugs, dietary supplements, diet changes and others. When dealing with an itchy dog, it is important to be patient and follow your veterinarian's plan, including giving the dog all prescribed treatments. In the long-run, your dog will have the best chance of making a full recovery if you follow a careful plan and rule out causes of itching in a logical order.