- Dr. Edward Kent Jr.
Welcoming a furry friend into the family often comes with great benefits. Pets can provide love and companionship, help reduce anxiety, teach responsibility and even get kids outside more.
But for some children, snuggling up to a dog or cat causes unpleasant allergic reactions. Dr. Edward Kent Jr., an allergist-immunologist with Timber Lane Allergy & Asthma Associates in South Burlington, debunks allergy myths and explains the treatments available to animal-loving families.
KIDS VT: Why are some people allergic to animals?
EDWARD KENT: An allergy is an undesired immunologic response. It develops over time, and once that inflammatory response is in place you run into trouble. Breathing in pollen, dust mites and animal dander — tiny bits of hair or skin shed by an animal — is not supposed to trigger the immune system. But if you have an allergic predilection, then your body considers them to be noxious invaders and your body makes allergic antibodies against them. The substances that trigger an allergic response tend to be proteins in the animal's dander, saliva and urine. Depending on what organ system is involved, you might be bothered by itchy eyes, a runny nose, congestion, sinus fullness or asthma symptoms.
KVT: Do allergic reactions vary from patient to patient?
EK: They vary based on the individual patient's sensitivity, but also with the intensity of the exposure, the nature of the exposure and the chronicity of the exposure, meaning whether you only come across the cat when you visit relatives on Thanksgiving, or whether you live with the cat.
KVT: Are dog and cat allergies the most common types?
EK: They are, because those are the most common pets we encounter. But any furred, warm-blooded animal, including rabbits, gerbils, hamsters and horses, are capable of triggering an allergic response.
KVT: Can children outgrow a pet allergy?
EK: They may become less symptomatic over time. That's because the immune system learns to put on the brakes and induce a tolerance to the exposure. But the pathway is still there. If an allergy is going to be "outgrown" this usually takes many years to occur.
KVT: If a child is allergic to cats, does that mean all cats or just certain breeds?
EK: All cats share a few common proteins that trigger the allergic response. If you are allergic to these proteins then you would be allergic to all cats. However, a mammal is a complex organism with many different proteins. There might be 10 or 20 proteins in the dander alone. Also the home in which they live may have accumulated different degrees of dander.
KVT: When breeders claim that certain breeds are hypoallergenic, what does that mean?
EK: There is no evidence to support a hypoallergenic breed. The idea is that if an animal does not shed fur it's less allergenic. For example, poodles and other hair dogs don't shed. And they probably contaminate the house less than breeds that shed fur. But the allergen is in the skin, and all breeds shed skin.
KVT: So does the breed matter when it comes to allergies?
EK: Allergic reactions are not predictable from breed to breed. One dog of a breed may cause more trouble for someone than another dog of the same breed. So you can't say that any one breed is certain to be better than another. There is no evidence that people will do better with a hair dog than a fur dog. In fact, it's been shown that people who are allergic to dogs have just as much trouble with dogs with fur as with dogs with hair.
KVT: Should kids who are allergic to pets avoid houses with them, or preemptively take medication?
EK: The decision on how to approach this is complicated. Is it a pet that the child already has an emotional attachment to? If you can have your symptoms controlled by just taking an antihistamine every now and then, this may be fine. Or, if you don't have pets yourself but you go to friends' houses who do, and you can take an antihistamine and be comfortable, then that may be an option. But if you have asthma and trouble breathing around animals, then the ante's been upped.
KVT: What about allergy shots?
EK: It all depends on the kind of symptoms you have. There are allergy shots you can get for cats and dogs that can be effective at reducing symptoms. They may not completely eliminate those symptoms, but they could reduce them significantly and this could be a way to help someone who has unavoidable exposure to cats and dogs.
KVT: How often do those shots need to be taken?
EK: You have to present the allergen protein to the immune system so that it can be broken down and lead to an induction of tolerance. So you give progressively increasing doses over the course of several months on a weekly basis. Once you've achieved the dose that has been associated with inducing a tolerance, you can then extend the interval to monthly. And then it's monthly for about three to five years. That's how long it takes to induce a tolerance that will be persistent. Avoiding the exposure if possible is usually preferable.