Dogs and winter season allergies

What are winter season allergies in dogs?

Winter season allergies can cause your dog to experience problems like itchy skin, sneezing, and watery eyes. These symptoms are typically triggered by indoor allergens like dust mites and mold. Like us, dogs are more exposed to these types of allergens during the winter because they spend more time indoors to avoid the cold. 

Fortunately, winter season allergies are often well-managed with treatment from your veterinarian. 

Symptoms of dogs with seasonal allergies

While allergies in humans often present as sneezing, runny nose, and itchy eyes, allergies in dogs manifest slightly differently. Although dogs with allergies can also experience sneezing and itchy eyes, they primarily exhibit changes to their skin. Symptoms in dogs with winter season allergies can vary depending on the severity and chronicity of their allergies. 

Common symptoms associated with seasonal allergies in dogs:

• Pruritus (aka itching): This can look like excessive scratching, licking, or chewing.
• Alopecia (aka hair loss)
• Erythema (aka redness)
• Hyperpigmentation (aka darkening of the skin)
• Lichenification (aka skin thickening)
• Secondary ear and skin infections: These can look like red bumps or pimple-like lesions, crusts, and flaky skin.
• Sneezing and reverse sneezing (due to allergic rhinitis)
• Red, itchy eyes and excessive tearing (due to allergic conjunctivitis)

What causes winter-season allergies in dogs?

Winter season allergies are caused by things in the environment (often airborne) that are more prevalent in the wintertime. 

There are three main types of allergies in dogs: flea allergy dermatitis, food allergies, and atopic dermatitis (or environmental allergies).

Winter-season allergies are mostly associated with atopic dermatitis. Flea allergy dermatitis and food allergies can also contribute to a dog’s allergic symptoms in the winter but do not typically flare during the winter. This is because fleas are less active during the colder months and symptoms of food allergy tend to be consistent year-round. Atopic dermatitis on the other hand tends to be seasonal because different allergens are more common during certain times of the year. Therefore, for the purposes of this article, we will discuss winter season allergies in terms of atopic dermatitis. 

Atopic dermatitis is influenced by multiple things including genetic and environmental factors. Certain breeds seem more predisposed to developing atopic dermatitis such as the Golden Retriever, West Highland White Terrier, and French Bulldog. 

Normal, healthy skin has a protective barrier function. In dogs with atopic dermatitis, this function is compromised which makes them more susceptible to absorbing environmental allergens. These environmental allergens activate the immune system, resulting in an inflammatory response. 

When considering what environmental allergens could trigger a reaction, we can divide them into outdoor and indoor sources. In the winter, outdoor sources of environmental allergens like pollen and grass are less significant. When considering winter allergies, the culprits are usually indoor allergens because dogs spend more time indoors when it is cold. Common indoor allergens include mold and dust mites. 

Diagnosing winter season allergies in dogs

If you notice any of the aforementioned symptoms or otherwise suspect your dog has allergies, make an appointment to see your veterinarian for evaluation.

Physical exam

Your veterinarian will begin by collecting a thorough history. Common questions will explore the symptoms, duration, progression, and response to any previous treatments. Your vet will also ask about things like diet and seasonality of symptoms. This history is crucial in guiding the diagnostic process.

Skin tests

After performing a physical exam on your dog, your veterinarian will recommend a series of skin tests such as flea combing, skin scraping, and microscopic evaluation of ear and skin samples. The goal is to rule out other skin conditions that could look similar to atopic dermatitis. If your dog has gastrointestinal signs in addition to skin issues, your veterinarian may also recommend a strict elimination diet trial to assess for food allergies. 

Intradermal test

Once your veterinarian diagnoses your dog with atopic dermatitis, then intradermal testing can be performed to identify what types of allergens your dog is most sensitive to. This is necessary if you want to pursue immunotherapy as a treatment option. 

Treating winter season allergies in dogs

If your dog has any secondary ear and skin infections, those will need to be treated. This is especially important because secondary infections can significantly increase your dog’s itchiness and discomfort. 

Treatment of allergies in dogs usually consists of a multimodal approach, meaning it combines multiple different methods. Therapy may combine topical, oral, and injectable medications. Please note that any medicine should be prescribed by your veterinarian.

These are examples of possible treatments your veterinarian may prescribe:

• Medicated shampoos: Dogs with allergies often require more frequent bathing. The key is contact time. Shampoo should be allowed to sit for 10 to 15 minutes before rinsing thoroughly.
• Mousses, sprays, and wipes: These are useful between baths.
• Creams and ointments: Topical therapy targets the skin directly and helps decrease the need for systemic medications.
• Antihistamines: May not be as effective at controlling itching.
• Omega-3 fatty acid supplements: Fish oil contains DHA and EPA which have anti-inflammatory effects.
• Corticosteroids: Corticosteroids have a rapid onset and broad anti-inflammatory effects but should only be used short-term to avoid unwanted side effects.
• Apoquel: Oral medication that reduces itching and inflammation.
• Cyclosporine: Immunosuppressive agent that is available in a capsule or liquid.
• Cytopoint: Injectable monoclonal antibody that reduces itching.
• Allergen-specific immunotherapy (aka “allergy shots”): Unlike the previously mentioned therapies which only address the symptoms, allergen-specific immunotherapy aims to address the problem with the immune system. It works by exposing your dog to allergens to increase his tolerance to them over time. 

Reducing exposure to potential allergens is also helpful. For winter season allergies specifically, it is important to clean the house regularly to help reduce things like mold and dust mites. This includes regular vacuuming and cleaning your humidifier. 

Atopic dermatitis is not curable and needs to be managed lifelong. Managing your dog’s allergies is important to prevent flares and the development of secondary ear and skin infections. The good news is that if your dog only experiences symptoms in the winter, he may only require treatment for a few months out of the year.