Atopic dermatitis in dogs and cats specifically refers to an environmental (inhalant or contact) or seasonal allergen that causes flare ups in companion pets that typically are genetically predisposed to this inflammatory response. Veterinarians and veterinary dermatologists concur on this definition.
To clear up any confusion, however, human atopic dermatitis is commonly referred to as eczema. The Mayo Clinic defines eczema as, “Healthy skin helps retain moisture and protects you from bacteria, irritants and allergens. Eczema is related to a gene variation that affects the skin’s ability to provide this protection. This allows your skin to be affected by environmental factors, irritants and allergens.”
The American Academy of Dermatology takes a more cautionary tone, “Researchers are still studying what causes eczema.” However, the association points out commonalities amongst patients suffering from eczema.
The association does state unequivocally, “Foods do not cause eczema. But some studies suggest that food allergies can make eczema worse. Children who have eczema often have food allergies to these foods — milk and foods that contain milk (e.g., yogurt and cheese), nuts, and shellfish.”
No cures exist for canine atopic dermatitis, feline atopic dermatitis, or eczema (human atopic dermatitis) at this time. The available tools are only treatment options to reduce inflammation.
Environmental Contributors to Atopic Dermatitis Flare Ups in Dogs and Cats
- Grass and weeds
- Plant pollens and trees
- House dust mites, fleas, other insects like cockroaches
- Mold and fungal spores, yeast
While fleas may not be considered as a true cause of atopic dermatitis flare ups, they can worsen the level of itching from environmental allergies. Bacterial and yeast overgrowths – as well as food sensitivities – can do the same.
Signs of Atopic Dermatitis in Dogs and Cats
- Scratch, chew, lick or rub areas of the body such as their paws, face and rear end
- Recurrent skin, ear, foot, and anal gland inflammation and infections
- So-called “interdigital cysts”
- Pruritus is the medical term for itchy behavior, which can cause hair loss and reddening and thickening of the skin
Visual diagnosis is possible with signs of atopic dermatitis in dogs and cats. However, definitive diagnosis as to the exact causative allergen can only be identified with either an intradermal (skin prick) test or serum (blood) draw. These tests look for increased levels of the IgE (or IgD) circulating in the blood or that are adhered to tissues.
For cats, the preferred test is run on serum.
While food sensitivities and fleas do not directly cause atopic dermatitis – they can exacerbate the symptoms – it is best to have your dog tested for these, too. The serum or intradermal tests mentioned above will cover fleas. Food sensitivities should be tested using NutriScan Food Sensitivity and Intolerance Test for Dogs, Cats and Horses.
Atopic Dermatitis Treatment Options for Dogs
Remember, there is no cure for canine atopic dermatitis. However, there are management techniques and treatment options.
More Natural Treatment Options
Avoid the allergen
This can be difficult with contact or inhalant allergens. However, if a concurrent food sensitivity is diagnosed, your companion dog should also avoid the offending foods.
Reduce the Contact Load and Potential Bacterial or Fungal Overgrowth
The goal is to get the contact allergen off the skin or paws as soon as possible. As well, bacteria or fungi overgrowth can occur because the skin is compromised from increased scratching or inflammation.
Bathe or wipe dogs down several times a week with one of these solutions:
- Green tea bag poultice or solution – Dr. Dodds and Hemopet prefer (especially for white and light-colored pets) this method. The green variety is preferred over white or black; the tannins and polyphenols are antioxidant, anti-microbial and anti-inflammatory
- Peppermint oil shampoo designed for dogs
- Tea tree oil shampoo also designed for dogs (always diluted to avoid toxicity)
- Povidone iodine (Betadine) – One of the Hemopet staff members is trying this with her dog. She puts her dog in a diluted povidone iodine solution for a few minutes and then wipes off his affected areas. She has noticed he has stopped licking his paws incessantly and consequently not scratching his face or body as much
You can also use calendula cream or oil, which is an all-natural anti-inflammatory. This is over-the-counter, but make sure it doesn’t have any hydrocortisone.
Suggested Conventional Treatment Options
You may have seen the commercials for injectable Dupixent (dupilumab) for human eczema. Dupilumab inhibits interleukin (IL) -4 and IL-13 cytokine‑induced responses, including the release of proinflammatory cytokines and chemokines and the antibody IgE.
Dogs do not have this exact treatment option, but have another type of cytokine targeted injectable option: Cytopoint (CADI). Cytopoint is a protein (monoclonal antibody) and directly binds to the cytokine, IL-31, which is the one associated with chronic itching. If the amount of scratching can lowered, the side effects of the flare ups are reduced.
A researcher noted that a few cases showed diminished response with each additional injection, suggesting that antibodies to Cytopoint were developing. [Drug tolerance occurs when higher doses of a drug are needed to produce a given response. When this develops rapidly (with only a few administrations of the drug) this is termed tachyphylaxis, a rapid decrease in response to repeated doses over a short time period.]
If drug tolerance occurs with Cytopoint for your companion dog, you may want to consider oclacitinib (Apoquel), which is an older treatment option. Oclacitinib modulates two Janus Kinase (JAK) enzymes. Once the JAKs are inhibited, inflammatory cytokines – that result in inflammation and itching – are slowed or stopped. The cytokines affected are interleukin-2 (IL-2), IL-4, IL-6, and IL-13 for allergy and inflammation; IL-31 is also affected. Dr. Dodds does not prefer use of this drug, as it blocks much of the immune cell’s normal cytokine responses, and when used for the long-term, can lead to a decrease in white blood cells and elevate liver values.
Neither Cytopoint or oclacitinib (Apoquel) should be used unless the other treatment options above do not work and then only in severe refractory cases.
Antibiotics are another option for bacterial overgrowth or hypersensitivity in the skin due to atopic dermatitis. However, antibiotics do lead to bacterial resistance and should only be used in severe cases or in attempts to get the overgrowth under control. In susceptible dog breeds like the German Shepherd or Doberman Pinscher, long term use of antibiotics for as long as 2-3 months may be needed to control these bacterial hypersensitivity reactions.
Conventional Treatment Options to Avoid
- Cyclosporin (Atopica) – a potent Immunosuppressant
- Topical or oral corticosteroids or glucocorticoids – side effects are common if used long term
- Immunotherapy – Immunotherapy should be utilized only if a diagnostic intradermal or serum-based IgE test was performed. Allergen-Specific Immunotherapy (ASIT) is given as an injection, or as a newer treatment option that puts a few drops under the tongue, called Sublingual Immunotherapy (SLIT). The formulations are specifically tailored to the individual pet and are quite pricey. The success rate for ASIT to alleviate symptoms is approximately 60-80% and SLIT has been around 60%. We believe that the success rates should be higher to be considered as warranted.
Treatment Options for Feline Atopic Dermatitis
Cats do not have as many cutting-edge treatment options as do dogs.
Avoiding the offending allergen is easier said than done particularly if the allergen is dust mites. Of course, regular cleaning will reduce this allergen.
Currently, cyclosporin, ASIT, and glucocorticoids are the only treatment options for cats afflicted with atopic dermatitis. If we were to choose one out of these three, it would be ASIT.
Oclacitinib has been given to cats, but is not approved by the U.S. Food and Drug Administration for use in cats. This is considered “off label” therapy.
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“Atopic Dermatitis in Dogs. “ VIN – Veterinary Partner, 26 Apr. 2018, https://veterinarypartner.vin.com/default.aspx?pid=19239&id=4951973.
Bajwa, Jangi. “Atopic dermatitis in cats.” The Canadian Veterinary Journal = La Revue Veterinaire Canadienne vol. 59,3 (2018): 311-313, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5819051/.
Becker, Karen. “Atopic Dermatitis in Dogs.” Healthy Pets, Mercola, 14 Aug. 2016, https://bit.ly/37p8ibM.
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Dodds, Jean. “Cytopoint for a Dog’s Itchy Skin.” Pet Health Resources Blog, Hemopet, 27 Jan. 2019, https://www.hemopet.org/cytopoint-dogs-itchy-skin/.
Dodds, Jean. “Wiping or Soaking a Dog’s Paws.” Pet Health Resources Blog, Hemopet, 19 May 2019, https://www.hemopet.org/dog-paw-wipe-soak/.
Moriello, Karen A. “Overview of Atopic Dermatitis – Integumentary System.” Merck Veterinary Manual, https://mrkmnls.co/35hfGVj.