Welcome to Animal Hospital of Lynnfield ONLINE!

Atopy: Allergies to Inhaled Substances

Allergies are just as common in dogs and cats as in people – about 1 in 10 pets is allergic to some degree. Some breeds of dogs are more prone to allergies than others. Inhalant allergy, called Atopy, is the most common form.

HOW DO PETS SHOW THEIR ALLERGIC SYMPTOMS?

Unlike people, whose symptoms of hayfever involve the eyes, nose and throat, symptoms in dogs and cats usually involve the skin. Itchy face, feet, and ears are the most common signs. Itching, redness and hair loss can eventually spread to the entire body.

WHAT CAUSES PETS TO HAVE ALLERGIES?

The tendency to develop allergies is inherited, which is why some breeds are more prone than others. Once your pet develops an allergic sensitivity to a substance, he or she will be allergic to it for life. Any time exposure to the substance occurs, an allergic reaction is triggered and symptoms appear. Common allergens (substances which trigger allergies) include pollens, mold and mildew spores, dust mites and wool.

Dogs and cats can also develop allergies to foods and to substances they lay on or that otherwise contact the skin. These forms of allergy are less common.

WHEN DO THESE REACTIONS DEVELOP?

Allergic reactions begin to develop at 6-24 months of age. Once the immune system is sensitized, the reaction itself can begin within a few minutes of exposure to the allergen. Most pets are allergic to more than one thing.

Pollen allergies often wax and wane with the seasons. Allergies to substances present in the home, like dust mites, molds and mildews, are more likely to be year ‘round.

Allergies gradually worsen with time. Many dogs do not have symptoms severe enough to be noticed until they are 3-5 years of age. Unlike atopy, food and contact allergies can begin at any age.

WHAT IF MY PET GOES UNTREATED?

The inflammation and itching lead to licking, biting and scratching. This can cause severe skin damage. Infection, either bacterial or fungal, can then set in. Not only is the allergic reaction very uncomfortable for your pet, but it leads to other problems as well.

HOW CAN I TELL IF MY PET IS ALLERGIC?

Some cases are easier to diagnose than others are. Skin mites, ear mites, flea allergy, food allergy and many other problems can show similar signs. Sometimes the secondary problems such as skin infection are severe enough to mask the underlying allergy problem. Your pet’s doctor will need a detailed history of your pet’s symptoms, including such things as: age at onset; seasonal occurrence; first signs of trouble; subsequent signs; and any correlation between the sensitivity and the amount of the exposure to various allergens.

Usually, the first experience with inhalant allergies corresponds with plant pollination – ragweed is a very common allergen in dogs just as in people. In time, however, seasonal patterns may be lost, as the patient becomes sensitive to dusts and other materials. Observations of flare-ups will help to determine which allergens are important.

WHAT CAN BE DONE TO GIVE MY PET RELIEF?

1. Avoidance: This, unfortunately, is not always possible. 300 miles out on the open ocean there are still pollens in the air! However, pets with allergies do best in homes with air conditioning, which filters the air and means more closed windows. They also do better with wood floors that catch less dust than carpeting. Wiping the feet and legs when your dog comes in from outside will reduce the pollen load he collects on his own body and then inhales while licking and chewing. Feathers, aerosols and smoke are examples of things that can be avoided.

2. Corticosteroids: These medications are the most effective at controlling symptoms. The relief they give is often dramatic. However, serious side effects can occur with long term use. We try to use them only as needed for short-term allergies. For long term problems we try to find other alternatives.

3. Antihistamines: These don’t work as well for skin symptoms as they do for the respiratory symptoms that people get. About 2/3 of dogs will get at least some benefit from them. Often we can reduce the amounts of corticosteroids needed by giving antihistamines as well. For mild allergies they may even be effective on their own. There are several different kinds and some dogs respond better to one than another. We often try two or three before setting on one that seems to help. Antihistamines rarely help much for cats.

4. Fatty Acid Supplements: These are also very helpful for some pets but not at all for others. They come in capsule or liquid form. Some pet foods have good levels of these vitamins in them already. Fatty acids have anti-inflammatory effects. They also are used by the body to make skin oils, which is helpful for itchy, allergic skin. Fatty acids can also reduce a pet’s needs for other medications, even when they aren’t enough to stop the allergic reaction on their own.

5. Hyposensitization: Hyposensitization is used when a patient’s allergies span the seasons or are year round; when symptoms are not controlled by reasonable amounts of medication; or when corticosteroids cannot be used for other health reasons. Allergy testing is first done, via blood or skin tests, to determine what substances the pet is allergic to. Then the pet is given allergen injections every 1-3 weeks by the owners at home to override the allergy response to those substances. Hyposensitization is usually effective but it is also expensive and requires a big commitment on the part of the owner.

6. Allergy Testing: Testing of your pet’s blood is possible. Measurement of circulating antibody levels to known allergens (food and pollens). This enables you and the Doctor to come up with realistic treatment plans based upon a working knowledge of what your pet seems to be most allergic to. The major benefit is that you are able to have some concrete guidelines as to what environmental and food items to avoid contact with. Talk with the doctor about this testing method.

WHAT IS THE BEST COURSE OF THERAPY FOR MY PET?

Therapy varies widely from patient to patient. A good working relationship between the pet owner and the veterinarian is needed to find the treatment regimen that works the best for particular dog or cat. There are so many different treatments available, and so many complicating factors such as fleas and bacterial infections, that there is no one best way to treat atopy.

Please call if you have any questions about your pet’s allergies, or if you think he or she is not responding well to treatment.