Hypoallergenic Dogs and Dog Allergies: FAQ

Hypoallergenic dogs have gotten a lot of buzz lately as the
Obama family searches for a dog to bring with them to the White House --
without triggering dog allergies in older Obama
daughter, Malia.

A quick glance at the Internet shows lots of web sites devoted to
"hypoallergenic dogs" and "hypoallergenic dog breeds." But no
dog may be free of potential allergens, cautions allergy and asthma expert Corinna Bowser, MD,
of Havertown, Pa.

WebMD talked with Bowser about hypoallergenic dogs and dog
allergies -- and what the Obamas might consider to help avoid triggering
Malia's dog allergy.

Is there such a thing as a hypoallergenic dog?

"I don't think there is such a thing as a hypoallergenic dog,"
Bowser tells WebMD.

She explains that the major allergen in dogs is a protein found in dog
serum, and dogs excrete that allergen in sweat and shed it from their skin.
"It also gets secreted into the saliva, and possibly a little bit in the
urine," Bowser says.

Since all dogs have that protein, no dog is completely allergy-free,
according to Bowser.

What about dog breeds?

Bowser says she didn't find much evidence in medical literature about dog
breeds being better or worse for allergies.

But she did find a German study, published this year, that tracked allergies
among people exposed to various dog breeds. "They said factors related to
individual dogs seem to influence the allergenicity more than breed or gender,
which I thought was interesting," says Bowser.

In other words, it was a dog-by-dog issue more than a breed-by-breed issue
in that particular study, which Bowser says is the only one she found that
involved specialized allergy tests .

Does the dog's size or hair length matter?

"The size of dog could matter in terms of the overall amount of
allergen," with smaller dogs contributing less allergen, says Bowser.

"Hair length could have something to do with how it spreads in the
house," Bowser says. She explains that shorter dog hairs may not stick as
much as long hair to furniture, clothes, and other surfaces, "so maybe the
allergen does not stick as much, but the amount of allergen should be the
same."

So are all dogs off limits to the Obamas?

Bowser has no ties to the Obamas, but she says that "if this was my
patient ... I would say it's probably better not to get a dog."

"Of course, now he [Obama] made the promise and he kind of has to,"
she says. So Bowser recommends doing two things before bringing a puppy home:
Dog-sit and see how Malia's allergies fare, and set some rules about how
they'll handle any allergy issues.

"What we tell our patients is draw an imaginary line in the sand. If the
child has an ER visit for asthma or needs significantly more medication , or whatever you want to determine as the
line, that's when the dog has to go. And set these rules ahead of time, because
then everybody knows that's when the dog has to go," Bowser says.

What can a family do once they've brought a dog home?

Here are Bowser's tips:

• Keep the dog out of the allergic child's bedroom, since the child spends a
  lot of time there.


• Wash your hands after petting the dog.


• Keep the house clean.


• Consider using an air purifier.

Bowser also mentions the "hygiene hypothesis," which holds that
exposure to animals and less-than-sterile environments may reduce the risk of
developing allergies.

Could a dog allergy fade?

Allergies to dogs and cats may shift over time, notes Bowser.

For instance, she says some patients who grew up with a dog develop symptoms
of dog allergies after being away from home for a long time, such as college
students returning home for the holidays. "They visit their parents for
Thanksgiving ... and they have symptoms where they never had symptoms
before," says Bowser.

"We know of certain allergens that are always bad for people with
allergies. For example, the dust mite or cockroach -- they're always bad. But
dog or cat are kind of in the gray zone," Bowser says, adding that she's
getting used to her husband's cat. "That's my experience," she says.
"I'm actually not really doing bad with this cat."

By Miranda Hitti
Reviewed by Brunilda Nazario
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