Seasonal allergies emerging
As tiny green, yellow and pink buds began painting tree branches a few weeks ago, Lindsey McVeigh decided it was time to see an allergy expert.
For years, McVeigh has used over-the-counter drugs to treat her sneezing, drippy nose and teary eyes. But this year, after a move to one of the USA's most notorious locales for allergies, she wanted allergy testing to help pinpoint the cause of her symptoms.
"I was going through boxes of tissues," says McVeigh, 30, of Falls Church, Va., near Washington, D.C.
Testing confirmed what McVeigh already suspected — that she has serious pollen allergies. At least 10% of Americans have seasonal allergies (to tree, grass and ragweed pollens), says Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health in Bethesda, Md. Another 10% suffer from year-round allergies (including dust and pets), he says.
Still, few people really understand what's happening to their bodies when pollen counts rise, and how to best treat them, Fauci says, and many don't try anything other than over-the-counter medications.
These are quite effective in people with mild symptoms, but much less effective for moderate and severe symptoms, he adds.
Allergic rhinitis afflicts an estimated 60 million people in the USA, says the American Academy of Allergy, Asthma & Immunology. And numbers are on the rise, says David Rosenstreich, director of the division of allergy and immunology in the department of medicine at Montefiore Medical Center in the Bronx, N.Y.
Elm, hickory, sycamore, walnut, olive, pecan, catalpa, ash, box elder, cottonwood, maple (red and silver), oak, poplar, willow, date palm, Phoenix palm.
Trees that do not tend to aggravate allergies include:
Crape myrtle, dogwood, fig, fir, palm, pear, plum, redbud, redwood.
Typical pollen seasons:
Though there is always overlap, with variation depending on where you live:
Summer : Grass
Climate change may play a role because as the earth warms up, pollen counts rise, but other factors may also affect the increase, including Western lifestyles, he says. "Antibiotic use, reduced infections and excessive cleanliness. Less exposure to dirt and dust. The cleaner your lifestyle, the worse allergies you tend to get. It has a lot to do with bacteria we are exposed to," Rosenstreich says. He adds that some research suggests allergies have risen with paved roads.
So what's happening when a pollen allergy rears its ugly head? A person is having an abnormal response, says allergist and immunologist Princess Ogbogu, assistant professor of medicine at Ohio State University in Columbus.
In people with a genetic predisposition for allergies, "certain proteins from pollens, called allergens, can induce the immune system to produce a specific type of antibody called IgE antibody," says Fauci.
IgE antibodies attach to the surface of various immune cells, such as mast cells in the nose and mouth and the lining of the bronchial tubes, says Rosenstreich. When exposed to pollens, an interaction with the IgE antibodies occurs and leads to a release of histamine and other substances from the cells. That causes symptoms such as mucous production, runny nose, sneezing and itchy eyes.
"Each person's immune system is very unique, and there are a lot of complex reactions," Ogbogu says. She says some people with birch tree and ragweed pollen allergies get oral allergy syndrome: The inside of the mouth and throat itches when they eat certain foods, such as orchard fruits and melon. But cooking de-natures the proteins, she says.
There are basically three key ways to treat allergies, says Rosenstreich: controlling your environment, taking medications and getting allergy shots, called immunotherapy.
Antihistamines (available over the counter and by prescription), nasal glucocorticoids (steroids available only by prescription) and antihistamine nasal sprays (prescription only) are safe and effective medicines, he says. Antihistamines reduce or prevent the effects of histamines.
About 20% of people with seasonal allergies do not get adequate relief with these medications, Fauci says, and they might benefit from allergy shots, which make a person's immune system tolerant to the allergen. New methods of immunotherapy, such as placing liquid allergens under the tongue instead of giving a series of injections, are being tested.
McVeigh says the antihistamine and nasal drops that her allergist prescribed were too pricey, so she picked up an over-the-counter antihistamine and monitors local pollen levels. "I have a cat and was concerned it was a pet allergy, so it's good to know it was pollen. Now I can read up on what to do to help it," McVeigh says.
Ogbogu adds that allergies "start burning out as you get older — by age 60 or 70, your immune system reacts less to seasonal allergens."