Canine Atopic Dermatitis: The Key to Reducing Itchiness is 'Avoidance Therapy'

If a dog shows symptoms of continuously scratching or licking its body, atopic dermatitis should be suspected. According to veterinarian Lee Tae-ho, atopic dermatitis refers to a condition where the immune system overreacts to harmless substances, causing inflammation and severe itching (pruritus) in the skin.

Itchiness is the key symptom and can appear anywhere on the body

The most representative symptom of an allergic reaction is pruritus, or itchiness. The video emphasizes that itchiness must accompany an allergic reaction. Even if redness or swelling occurs, if the pet does not itch the affected area, the possibility of an allergy is very low. In other words, it can only be called an allergy if the act of itching is visible. In the case of cats, they tend not to show their itching clearly to owners, but for dogs, it is mostly observable.

Atopic dermatitis is not limited to a specific area and can appear anywhere on the body. However, symptoms are frequently identified around the mouth, ears, armpits, inner elbows (cubital), between the toes, and the groin. While allergies themselves do not cause hair loss, if skin immunity drops due to itching, secondary infections caused by bacteria or yeast (such as Malassezia) can occur. In such cases, symptoms like hair loss, foul odors, and discharge may accompany the condition.

Rather than being a congenital disease one is born with, allergy has a strong acquired nature, where the immune response is triggered by exposure to specific antigens during life. It often begins from a point after 6 months to 1 year of age, and it is rare for new allergies to develop in middle-aged or senior dogs. However, it can be triggered by genetic predispositions or environmental factors.

Do not blindly trust blood tests; diagnosis must follow the exclusion of other diseases

Many owners believe that allergies can be definitively diagnosed through blood tests, but this is half true and half false. The video explains that a high amount of a specific antibody (IgE) in the blood does not necessarily mean a diagnosis of allergy. Blood tests can be used to find the cause of an allergy to plan immunotherapy (a treatment that desensitizes the immune system by injecting small amounts of antigens) and are meaningful in confirming the probability of exposure to specific antigens. A blood test alone cannot conclude whether an allergy exists.

For an accurate diagnosis, other diseases that cause symptoms similar to allergies, such as parasite infections or secondary infections caused by bacteria or yeast, must first be excluded. Especially in the case of bacterial infections, an antibiotic susceptibility test is conducted to check which antibiotic is effective. Only when these other diseases are all excluded and continuous itching, swelling, and redness are confirmed can it finally be diagnosed as an allergy.

'Avoidance Therapy' that blocks food and environmental causes is the key to treatment

Allergy is a disease that must be managed steadily, rather than being completely cured like hypertension. The goal of treatment is to control symptoms with the minimum amount of medication while maintaining the pet's quality of life. When symptoms are severe, emergency measures such as taking medication or applying ointments are necessary, but during normal times, effort is needed to find the cause of the allergy and manage it so that exposure does not occur. The most effective method for this is 'avoidance therapy,' which avoids the cause.

If a food allergy is suspected, the protein source must be identified and blocked. The video presents two methods. First is to feed 'hydrolyzed food,' in which protein molecules are broken down into small pieces, for about 8 weeks and observe changes in symptoms. During this period, accurate confirmation is only possible if all other food intake, including snacks, is completely restricted. Second is to try feeding new protein sources that have not been encountered before, such as kangaroo meat or horse meat.

If symptoms persist even after food restriction, environmental allergies such as mites should be suspected. Since house dust mites are difficult to completely remove from daily life, regular bathing or the use of medicated shampoos can be helpful along with medication management. Medicated shampoos are effective in reducing secondary infections. A point of caution is the reckless application of ointments used by humans. This is because the steroid components included in ointments can cause side effects in the pet, and if the pet licks the applied area, the components can be absorbed into the body. Therefore, when using topical preparations (ointments, sprays), care must be taken so that the pet does not lick.