Why Is My Dog Chewing on His Skin & Pulling Out His Hair?

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Your vet might conduct skin tests to determine the cause of your dog's allergy.
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If your dog is pulling hair out of his tail or chewing his skin, it's likely that he's suffering from some sort of allergy. Chewing and scratching is a common reaction to a few different things, so it is worth investigating some factors in your dog's life to determine the cause. Allergies to fleas, food, shampoo, or something else in the environment could result in this behavior.

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Dog chewing hair off leg

According to SkinVet Clinic, a dog pulling hair out, skin chewing, or constantly scratching likely has atopic dermatitis, or chronic itching. This can be caused by an allergic reaction to something. The itching seems to be concentrated on the face and the feet.

This is why it is common to see a dog chewing hair off her leg or scratching her legs a lot. In addition to the original irritation of the allergy, the constant licking, chewing, and scratching causes even more skin damage. If your vet needs to investigate the cause of the allergy, he will likely recommend switching food, switching soap or shampoo, or conducting allergy tests.


An allergy test could mean injecting a few common allergens into the skin. If red swelling develops, it is interpreted as an allergy to that substance. Alternatively, allergens can be dripped onto the surface of a dog's bare skin with similar results. Sometimes, blood, saliva, or hair can be tested.

Flea allergy dermatitis

VCA Hospitals says flea allergy dermatitis (FAD) is a leading cause of allergic reactions in dogs. A single flea bite can cause itching for days for a dog who is allergic to fleas. Even if you don't actively see fleas on your dog, he could still be bitten. Fleas are not always on the dog unless they are actually feeding.


FAD typically appears between age two and five in most dogs. A common sign of a flea allergy is a dog pulling hair out of the tail area from the base of the tail up to the middle of the back and down the rear legs. Treatment for a flea allergy typically starts with a commitment to flea control in order to keep fleas from biting your dog.

Food allergies in dogs

A food allergy is actually pretty common in dogs, according to VCA Hospitals. Dairy products in the food can trigger allergies, as can such wholesome ingredients as beef, chicken, eggs, soy, or wheat.


Food allergy or food hypersensitivity can develop at almost any age. To test for a food allergy, your veterinarian will have you make strict changes to your dog's diet for a period of time. She will work with you to develop a special diet, and your dog must eat this exclusively for a while in order to eliminate the problematic ingredients. Even things like vitamins must be considered as part of the elimination test.

Home remedies for dog itching

If you know what your dog is allergic to, sometimes the best home remedy for a dog pulling hair out is to avoid the allergens if at all possible. Other treatments are usually necessary, and this might include anti-inflammatory medicines or topical shampoos or creams that can bring relief to her itchy skin.


If the cause of the itching is a bacteria or fungus, ointments or other medications that are anti-bacterial or anti-fungal would be important. The first step is to determine why your dog is chewing hair off her leg or pulling hair out of her tail.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.