ANIMAL ALLERGY
Furry pets are much-loved members of many households. Over one half of homes in the United States have a cat and/or a dog. Unfortunately, about three to ten percent of Americans are allergic to pets. Family members and others who enter your home may suffer from animal allergy. Symptoms may include itchy, teary, swollen, red eyes and eyelids and/or a runny, itchy, congested nose. Susceptible people might develop symptoms of coughing, wheezing, and/or shortness of breath. Occasionally, sensitive people will develop hives at the site of contact with their pet or their pet's saliva.
Some people who are allergic to their own pets have no immediate worsening of their symptoms when near their pets. Instead they suffer from constant low-grade symptoms that only clear up after days or weeks away from the house. More sensitive individuals often have difficulty controlling their symptoms even with medication. Complications of pet allergy can include chronic sinus headaches and infections, nasal polyps and asthma.
Most people think pet fur or hair is the problem. Pet allergy symptoms actually result from exposure to animal proteins found in the pet's skin, saliva and urine. While the fur may be coated with proteins deposited from dried saliva, it is the dander that is the major source of pet allergen. Dander is the layer of dead skin, rich in animal protein, which is continuously shed. Sebaceous (oil producing) glands in the skin also produce these protein allergens. Male cats have, on average, greater amounts of sebaceous secretions and therefore are more allergenic than female or neutered male cats. This is a result of testosterone hormone effects on sebaceous glands.
Pet dander can cause allergy symptoms through direct contact or by transfer of the dander to the eye, nose or skin. However, most symptoms are caused by airborne dander that comes into contact with the mucous membranes of the eyes and nose. Animal dander can also be inhaled into the bronchial tubes. Allergenic proteins are found in homes for up to 6 months or more after a pet has been removed. Low levels of animal dander have even been found in homes without pets. These low levels may be caused by a pet owned by a previous occupant or by someone who inadvertently transports animal dander into the home on his/her clothes and hair. Common heating or air conditioning systems in apartment buildings may also spread pet allergens if some of the residents have pets. These low levels of pet dander exposure can cause chronic symptoms in sensitive people. Allergic individuals can also have symptoms in school and other places where pets are not directly present. Unfortunately, there are no "non-allergenic," or "hypoallergenic" breeds of cats or dogs. It is a myth that short haired animals are not allergenic. Although certain breeds may be more or less allergenic for some people, there are no "safe" furry pets if you are sensitive.
Did you know that people are twice as likely to be allergic to cats as they are to dogs? There are several possible explanations for this:
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Many people are so sensitive to cats that as soon as they enter a home with cat dander, they immediately experience severe symptoms. This explosive response can occur, less commonly, with dog dander exposure.
Animals other than dogs and cats can cause allergy symptoms. Guinea pigs and gerbils have strong allergens in their dander and their urine. Laboratory workers, zoo personnel, and veterinarians may encounter severe difficulty with allergy to other animals including horses, rodents, and less commonly, the large cats (lions and tigers) and primates such as monkeys. Bird feathers and droppings can also cause allergy symptoms. People with mold allergy can have symptoms due to bird droppings and accumulation of mold in the cage (dust can also be a problem). Fish tanks can cause symptoms because of mold growth.
The best way to control pet dander allergy is to remove the pet from the home environment. For many people, however, removing the family pet is difficult and emotionally painful. When it is
impossible to remove the pet, we recommend several measures that may reduce your exposure to animal dander and allow you to live with your pet:
1. Eliminate Animal Allergen Hideouts
Aside from the pet, carpets are the biggest reservoir source in the home for cat and dog allergen. The more carpeted surface you have, the more allergen there will be in the air. Upholstered furniture is also a problem. Walls can also be coated with allergen and should be washed periodically. Avoid purchasing used items from homes with pets since this furniture may be a rich source of animal dander. Be aware that any significant source of animal allergen can be a problem if it is near the intake of a forced air heating system or within the system itself. Avoid putting litter boxes near the air intake vents.
2. Remove Allergen From Your House
Frequent vacuuming will help. It is important to use a vacuum that has a microfiltration bag or is HEPA filter equipped (see our dust mite handout). Although good ventilation may reduce dander levels, it may cause problems during the pollen seasons if you or a family member is pollen allergic. Placing a HEPA filter air cleaner in the home is an important way to control animal dander and pollen exposure (see our handout on air cleaners.)
3. Remove Allergen From Your Pet
There are several scientific studies that show that washing your pet weekly will reduce the allergen load that it carries. In one study, airborne allergen was reduced by 85%. This is a difficult task, though it may be easier if you start washing the pet as a puppy or a kitten. Products like Allerpet (available at local pet stores) claim to decrease allergen if used regularly. It is not yet clear how effective these products are. Of course, washing your pet is best left to a family member who is not sensitive to animals.
4. Keep the Pet Out of Your Bedroom
This can be best accomplished by keeping the door to the room closed at all times. Wireless fence systems can be installed indoors to keep the animal out of certain areas of the house, including the bedroom. There are also devices that emit sound waves that are inaudible to humans, but keep dogs and cats at a distance (Comtrad Industries 1-800-704-1211). Of course, the job of litter care should be left to someone without pet allergy. There are self cleaning litter boxes available that may be of benefit (Comtrad Industries-See above). You can also ask one of The Asthma Center physicians about finding out levels of cat dander in your home.
5. Medical Treatment and/or Allergy Injections
Despite these measures, symptoms often persist. If this is the case, both allergy medications and/or allergy injection treatments may help. Newer anti-allergy medications have fewer side effects and work very well. They include non-sedating antihistamines and nasal sprays (containing cromolyn, corticosteroids, or antihistamines). For symptoms involving the eyes, drops containing similar medications are also very helpful. People with allergic asthma can use inhalers containing cromolyn, bronchodilators, or inhaled corticosteroids. New asthma medications called leukotriene modifiers (Singulaire', Accolate', and Zyflo') can also help some people.
Another form of treatment involves allergy injections, also known as immunotherapy. A series of injections containing allergy-causing protein (cat or dog) is given regularly. This form of treatment is highly recommended if a pet is in the home and causing frequent symptoms. Allergy shots are given as long as you are still exposed to the animal(s). While scientific studies have shown this to be a very effective form of therapy in treating cat and dog dander allergy, it is more effective in treating cat allergy. Results may be permanent.
In summary, animal dander allergy can significantly contribute to respiratory problems involving the sinuses, nasal passages, and eyes, as well as cause upper respiratory tract problems resulting in asthma. These problems can significantly diminish one's quality of life despite medical treatment. For some people, it is even more serious, leading to recurrent acute asthma episodes that can be life threatening, emergency room visits and hospitalizations. The good news is that most animal allergic people can keep their symptoms under control if they know the facts.