Fleas, ticks, mites, skin infections and allergic reactions cause scratching in dogs, according to PetMD. Dogs commonly experience seasonal and environmental allergies due to grasses, weeds and trees. Some dogs have food allergies that trigger inflammation and itching of the skin.
Nutritional allergies in dogs are often caused by specific protein sources, such as chicken, fish or dairy, or a reaction to grains, such as wheat and corn, explains PetMD. While environmental allergies are most common in the warmer months, dogs that live in locations with warm or humid winters can suffer reactions to blooming plants in any season. Microscopic insects, including mange, feed on a dog’s skin causing inflammation and skin lesions that can progress to bacterial and yeast infections, especially on body areas with sparse fur.
Fleas and ticks feed on a dog’s blood, and their saliva creates irritation at the point of entry on the skin that causes a dog to scratch and bite, notes PetMD. Because dogs can injure themselves through intense and repetitive scratching, licking and chewing, working with a veterinarian to diagnose and treat the specific cause of the irritation is important. Elimination diets are often used to determine nutritional allergies, and regular grooming and indoor air filters help reduce allergic dermatitis from environmental allergens. Tick and flea preventatives treat insect infestations, and cases of severe demodectic mange may require oral medications, injections or special dips.