Symptoms may vary depending on the type of allergy. For food allergies, the following are characteristic:
- Itching of the skin, leading to irritation, licking, scratching, in dogs with light fur, saliva staining is possible;
- Rash, usually on the face, abdomen, front paws;
- Sometimes sneezing, nasal and ocular discharge;
- In 20% of cases, gastrointestinal disorders such as vomiting, diarrhea, though these symptoms are more typical of food intolerance, the mechanism of which differs from an allergic response.

Flea allergy usually manifests seasonally, in summer and autumn. The main symptoms are intense itching, restlessness, loss of appetite, rashes, often with suppuration, formation of crusts. An indirect sign is black dandruff, which can appear even in animals not allergic to flea bites. Infectious allergy presents similar symptoms, but usually the symptoms of the underlying disease come to the fore.

Chemical allergy also manifests with skin reactions and itching, possible redness and peeling of paw pads, hair loss. In the case of contact dermatitis, manifestations are localized in areas of contact with the irritant. In atopic dermatitis, the symptoms are similar but more pronounced - hair loss, inflammation of paw pads, formation of pustules, redness of mucous membranes.

Reaction to medications develops rapidly and acutely, rashes can cover the entire body, the face reddens, salivation increases. In severe cases, seizures and anaphylactic shock are possible.

Additional manifestations of allergy include:
- Otitis (reaction to ear parasites) - head shaking, whining, painful reaction to ear touch, abundant ear discharge with an unpleasant odor;
- Acute moist dermatitis - appearance of red, moist, hairless spots, eczema;
- Black skin syndrome (can be caused not only by hypersensitivity, but also by endocrine disorders, mechanical skin abrasion).

Since the clinical picture is similar in various types of allergies, complex examination and various analyses are necessary for accurate diagnosis. It is also important to analyze what new elements have appeared in the dog's environment and diet recently.

Treatment of allergy in dogs. The main treatment strategy is to eliminate the cause. For insect allergies, the use of flea control products in the form of sprays, powders, shampoos, dips, and collars with methoprene is recommended. It is important to treat not only the skin and coat but also the living environment - bedding, carpets, cracks in wooden floors, yard. For infectious allergies, treatment of the underlying disease is necessary, and for chemical allergies, avoiding contact with the irritant if possible. In case of a reaction to medications, immediate medical attention is required to select and administer an antidote.

In the case of atopic dermatitis, it is sometimes impossible to isolate the animal from the allergen, in which case symptomatic therapy is used. Also, in case of atopic nature of the disease, diet therapy is mandatory. The best option is to choose a quality hypoallergenic ready-made food.

The basis of treatment for food allergy is the exclusion diet. Products or food that cause a reaction should be prohibited, and it is desirable to avoid potential allergens, transferring the pet to hypoallergenic food. However, there is a risk of developing hypersensitivity to new products or food, in which case a new diet will have to be selected again.