Canine Atopy

" Canine Atopy is a condition where your dog's skin is reacting to something in the environment (called hypersensitivity) such as weed pollen, grass, mold, dust or mites found in the home. The result is a condition called canine atopic dermatitis which clinically appears as a rash accompanied by skin itch. Symptoms can appear in one location or several. The condition, also referred to as AD, is thought to affect between 3% and 15% of dogs. There are several effective treatments for canine atopy including prescription and over the counter medications and dietary supplements. "

This condition is due to a hypersensitivity to aeroallergens such as pollens, house dust mites, or mold spores. Allergy related problems could vary with the change in seasons and then gradually start to appear year round.

Atopy can affect different areas of the body, but is primarily found on the ears, paws, stomach and legs. In the past few years treatments have greatly improved with several good options available including prescription medications, over the counter and natural approaches.

Dog Atopy Symptoms

Symptoms of canine atopy start to appear between the ages of 6 months to 3 years. Symptoms include dog skin itch (pruritus) and rash (erythema). Symptoms that are associated with atopy in dogs include:

• changes in the coat or hair
• excessive sweating (hyperhidrosis)
• oily skin (seborrhea)
• skin licking, particularly on the legs (acrol lick dermatitis)
• bacterial skin infection due to itching (pyrotraumatic dermatitis)
• canine hives (urticaria)
• nasal discharge and inflammation (rhinitis)
• conjunctivitis

Dog skin diseases that are similar to atopy include parasite problems such as scabies, bacterial or fungal skin infection, allergies such as those caused by food or fleas). Diseases which can cause similar symptoms include pancreatic disease (hepatocutaneous syndrome) and tumor formation on the outer layer of the skin (called canine epitheliotropic lymphoma).

Canine Atopy Diagnosis

After ruling out the other possible causes mentioned above, a veterinarian could test the dog for various allergens using an ELISA or RAST test in the same way humans are tested for allergies. Often this testing is only done if it is necessary to identify the specific allergen causing the problem, which is the case if immunotherapy (allergy shots) is used.

Dog Atopy Treatment

There are several treatments that have shown to be effective as described below.

At the start of treatment, and to bring some relief to the dog, symptoms are treated with corticosteroids and antihistamines. If a dog has s skin infection that contains pus (called superficial pyoderma), then antibiotics are prescribed for 3 weeks along with the use of an anti-bacterial shampoo such as Clinical Care. Also, cool water alone will have a soothing effect and help to wash away any allergens.

If this initial approach does not work, then many of the following are tried until the problem is resolved.

Oatmeal Bath - Dog shampoos such as Lambert K that contain colloidal oatmeal can provide relief from itch. It is not completely understood why, but oatmeal based products have a soothing effect on the skin.

Pramoxine - this is a topical spray ingredient that has become more popular in veterinary medicine since it doesn't have the toxicity associated with other products such as lidocaine. It is available in over the counter products such as Dermal Soothe Anti-Itch Spray.

Lime sulfur dips - these are safe for dogs and are particularly useful when dogs cannot tolerate or use corticosteriods or antihistamines. They are completely safe and available over the counter from companies such as Dermisil.

Linoleic Acid Shampoo- Allermyl, relatively new shampoo by Virbac has linoleic acid as an active ingredient. It works by improving the ability of the skin to resist the absorption of allergens, referred to strengthening the skin barrier.

Topical Corticosteroid Shampoos and Conditioners - These products are very effective in human medicine and are now available for dogs in shampoos, creams and ointments. One popular shampoo with 1% hydrocortisone and oatmeal is CortiSoothe.

There is also a leave on condition available called ResiCort, that is not rinsed off the dog. A clinical study demonstrated that when this product is applied to dog skin 2x per week for 6 weeks, skin condition returned to normal levels in terms of allergic response. If used in small breed dogs, consult a veterinarian as inflamed skin will increase the absorption of hydrocortisone.

Glucocorticoid spray - the active ingredient triamcinolone (.15%) was shown in a clinical study to reduce a "significant reduction in skin itch and irritation in 67% of dogs treated. It is available via prescription in Genesis Topical Spray.

Cyclosporine (Atopica®) topical treatment - has been shown to be effective. The atopy may return after treatment, although it is common and acceptable to go on and off treatment. Side effects include vomiting and diarrhea.

Topical Immunomodulators (TIMs) - are a new class of drugs that have been approved in humans for the treatment of atopic dermatitis. The initial approved formulation, Tacrolimus, has also been shown effective in dogs with atopic dermatitis.

Initially, treatment is a light application of the ointment or cream until it is completely rubbed in twice daily for two weeks. If a response is seen the frequency may be lowered to once daily or less. Side effects are minimal and have been limited to irritable behavior.

Interferons (INF) - available under the trade name Roferon-A®. This drug is given to your dog orally with limited results on long term effects.

Essential Fatty Acid Supplements for Dogs with Atopy

Essential fatty acids (Omega-3, Omega-6) such as those found in natural fish oil have produced improvement in dogs being studied including reduced levels of skin itch and improved coat quality. Other studies of dog's taking DVM 3V Caps, an essential fatty acid supplement also showed improvement in 11% to 27% of dogs.

Side effects from fish oil supplements are rare, but are possible. These include gas, diarrhea, weight gain, bad breath (smells like fish) and pancreatitis.

Immunotherapy for Canine Atopy

It may be necessary to reduce a dogs sensitivity to specific allergens which is the treatment goal of immunotherapy. In humans, allergy shots are a form of immunotherapy. In dogs a schedule is set based on how well the dog responds to allergy treatment. It can take from 3 to 6 months to show any results to this approach.

Have A Question about Your Dog's Skin Condition or Do You Have a Helpful Story to Share?

Do you have a question or comment? Share it!

Our editors will pick 1 question to answer each week. Please include your dog's age, breed, medical history and if possible, a picture of the condition.

We will do our best to get back to you quickly (it depends on how many questions we receive each day). If you do require an immediate response we suggest using this online dog veterinary service that is available now.

References for Canine Atopy

Canine Atopic Dermatitis
Clinical Disease and Diagnosis
Randall C,. Thomas DVM Dip ADVD
Caolina Veterinary Specialists
Charlotte, NC

Canine Atopic Dermatitis
Old and New Therapies
Randall C. Thomas, DVM, Dip. ACVD