Atopy in Dogs: Recognizing Itching, Diagnosis, and Modern Treatments

What is atopy in dogs?

Atopy (canine atopic dermatitis, cAD) is a chronic inflammatory skin condition with a genetic basis in which the immune system reacts hypersensitively to environmental allergens—primarily house dust mites, grass and tree pollen, mold, and storage mites. The reaction occurs via IgE-mediated sensitization: exposure to allergens leads to the release of inflammatory mediators in the skin, which cause intense itching.

Atopy is one of the most common skin conditions in dogs: an estimated 10% of all dogs are affected. It cannot be cured, but it can be effectively managed.

Background + Scientific Context

Eisenschenk et al. (2024, Veterinary Dermatology, PubMed 38095285) formulated the updated definition of cAD on behalf of the ICADA (International Committee on Allergic Diseases of Animals): a genetically predisposed, inflammatory, and pruritic skin disease with characteristic clinical features associated with IgE antibodies against environmental allergens. The ICADA treatment guidelines (Olivry et al. 2015, BMC Veterinary Research, PubMed 26276051) remain the standard of care and distinguish between acute and chronic phases with corresponding treatment options.

Van Brussel et al. (2021, Veterinary Dermatology, PubMed 34180084) demonstrated in a placebo-controlled RCT that lokivetmab (Cytopoint)—a monoclonal antibody against interleukin-31, the key itch molecule—significantly and rapidly reduces itching in dogs with allergic dermatitis. Mueller (2023, Journal of the American Veterinary Medical Association, PubMed 36940185) confirmed in a systematic review that allergen-specific immunotherapy (ASIT) is the only causal treatment for cAD and achieves clinically relevant improvement in 50–70% of dogs.

Vitomalia-Position

Atopy is one of the most common chronic conditions for which pet owners resort to “anti-itch medications” without a complete diagnosis. We emphasize: symptom control without a diagnosis is not a treatment for atopy. Before using oclacitinib or lokivetmab, flea bite allergy, food allergy, and other causes should be ruled out. We support modern, well-tolerated biologics (lokivetmab) as a sensible long-term option—and ASIT as the only causal therapy when specific allergen identification is possible.

When does atopy become a concern in dogs?

• For dogs with chronic, recurring itching, especially on the paws, ears, armpits, groin, and belly
• For seasonal itching (pollen allergy) or year-round symptoms (dust mites)
• In cases of recurrent anal gland infections, atopy is a known risk factor
• In cases of recurrent otitis externa without a primary bacterial cause
• For alopecia caused by secondary pyoderma or excessive licking/chewing
• Breeds known to be predisposed to atopy: West Highland White Terrier, Labrador Retriever, Golden Retriever, Boxer, Bulldog breeds, Cocker Spaniel, Dalmatian

Practical application

Typical distribution of itchy areas in cAD:

• Paws (licking, chewing between the toes)
• Ears (otitis externa as a common initial manifestation)
• Face, lips, periorbital region
• Underarms and groin
• Perianal and genital region

Diagnostic pathway (ICADA recommendation):

1. Rule out flea bite allergy (consistent flea prevention for 8–12 weeks)
2. Rule out food allergies (8–12-week elimination diet)
3. Apply the clinical ICADA criteria (Favrot criteria)
4. For a diagnosis of cAD: allergen-specific testing (intradermal or serological IgE testing) to determine eligibility for ASIT

Overview of treatment options:

Therapy	Mechanism of action	Application
Lokivetmab (Cytopoint)	Anti-IL-31 antibody	Acute + Long-term, monthly injection
Oclacitinib (Apoquel)	JAK1 Inhibitor	Acute + Long-term, daily oral
Cyclosporine (Atopica)	immunosuppressant	Long-term, taken orally daily
Corticosteroids	immunosuppressant	Short-term therapy (acute flare-up)
ASIT (Immunotherapy)	Hyposensitization	Causal, long-term, injection, or sublingual

Common Mistakes & Myths

• “Cortisone is the best solution.” In our view, this is a myth that still persists all too often in everyday practice: Cortisone is frequently administered too quickly and unnecessarily, even though it has a significant profile of side effects (polyuria, polydipsia, risk of Cushing’s syndrome, immunosuppression, skin thinning). It can help—and when other options no longer work, targeted and closely monitored cortisone therapy is justifiable. But we reject it as a first-line treatment and for long-term use. Modern alternatives such as Lokivetmab (Cytopoint) and Oclacitinib (Apoquel) are better suited for long-term treatment and have more favorable safety profiles.
• “Hypoallergenic food cures atopy.” Changing the diet is only helpful if there is a concurrent food allergy (which may coexist). Environmental allergen-induced cAD is not affected by diet.
• “Atopic dermatitis doesn’t just go away on its own.” In many cases, atopic dermatitis worsens with age and the range of allergens increases—it doesn’t simply go away. Early diagnosis and treatment prevent secondary infections and chronic skin changes.

Current State of Research in 2026

The ICADA (2024) has updated the definition of cAD to incorporate new findings on skin barrier dysfunction and microbiome dysbiosis. Biologic therapies (lokivetmab) and JAK inhibitors (oclacitinib) have transformed the treatment of atopy. ASIT remains the only causal treatment option; research on sublingual immunotherapy (SLIT) for dogs is increasing. Microbiome interventions and new biologics (anti-IL-13, anti-IL-4Rα) are currently being tested.

Frequently Asked Questions

How can I tell if my dog has atopy?

A typical scenario: The dog repeatedly licks, scratches, or chews at its paws, ears, armpits, belly, or face. This often starts seasonally but later occurs year-round. Redness, scabs, and secondary infections follow. Diagnosis requires a veterinarian to rule out flea bite allergy and food allergy.

What is the difference between atopy and a food allergy?

Atopy is triggered by environmental allergens (pollen, dust mites); food allergies are triggered by protein sources in the diet. Both cause itching, often in similar areas. They can be distinguished using an elimination diet (for food allergies) or an allergen-specific IgE test (for atopy). Both conditions can occur simultaneously.

Can atopy in dogs be cured?

No — cAD is a genetic, lifelong condition. Allergen-specific immunotherapy (ASIT) can lead to clinically significant improvement in 50–70% of dogs; complete remission is rare. Symptom control using modern therapies allows for a good quality of life.

Related terms

• Dog Allergies
• Dog Food Allergy
• Flea Infestation in Dogs
• Alopecia in Dogs
• Anal glands in dogs
• Itchy Dog

Sources & Further Reading

1. Olivry, T., DeBoer, D. J., Favrot, C., et al. (2015). Treatment of canine atopic dermatitis: 2015 updated guidelines from the International Committee on Allergic Diseases of Animals (ICADA). BMC Veterinary Research, 11, 210. https://pubmed.ncbi.nlm.nih.gov/26276051/

2. Eisenschenk, M. C., Hensel, P., Saridomichelakis, M. N., et al. (2024). Introduction to the ICADA 2023 canine atopic dermatitis pathogenesis review articles and updated definition. Veterinary Dermatology, 35(1), 3–4. https://pubmed.ncbi.nlm.nih.gov/38095285/

3. Van Brussel, L., Moyaert, H., Escalada, M., Mahabir, S. P., & Stegemann, M. R. (2021). A masked, randomised clinical trial evaluating the efficacy and safety of lokivetmab compared to saline control in client-owned dogs with allergic dermatitis. Veterinary Dermatology, 32(5), 477–e131. https://pubmed.ncbi.nlm.nih.gov/34180084/

4. Mueller, R. S. (2023). A systematic review of allergen immunotherapy, a successful therapy for canine atopic dermatitis and feline atopic skin syndrome. Journal of the American Veterinary Medical Association, 261(S1), S30–S35. https://pubmed.ncbi.nlm.nih.gov/36940185/