Some 35 million Americans suffer the unwanted return of the burning eyes, sneezing, sniffles, chapped nostrils and itchiness of allergic rhinitis, or hay fever, each year. While most people associate allergies with the blooming trees of early spring, autumn, with its rampant ragweed and outdoor molds, can spell even more misery for millions. If you’re one of them, MSNBC’s answers to your frequently asked questions on the other sneezing season.
What causes fall allergies?
For many, early fall brings on miserable seasonal allergies. The main culprits are mold spores, ragweed pollen and other weeds.
Ragweed — a yellow-flowering weed found along highways, vacant lots and fields — blooms from mid-August to the first frost. It’s most prevalent throughout the Northeast and Midwest, but almost no place in the United States is ragweed-free. Each ragweed plant produces an average of one billion pollen grains per season. The pollen can travel up to 400 miles so you may be affected by ragweed even if doesn’t grow nearby.
Other weeds such as cockleweed, mugwort, dock, amaranth, sagebrush, pigweed and tumbleweed also cause fall sniffles.
Molds, which produce airborne spores that trigger allergies in many people, are out in full force during the autumn months. Outdoor molds become plentiful in the fall in gutters, soil, rotten wood and fallen leaves. Damp fall weather also encourages the growth of molds inside the home in places like bathrooms, kitchens, basements, carpets and houseplants.
There are also some trees and grasses that pollinate in the fall, including cedar elm, September elm, fountain grass and wild mustard.
How can fall allergies be avoided?
To reduce your exposure to ragweed and mold:
- Keep windows closed at night to prevent ragweed pollen and mold spores from drifting into your home.
- Keep the yard free of fallen leaves, where molds can thrive.
- Avoid yardwork that increases exposure to pollens and molds, such as mowing, raking or weeding. If you must do yardwork, wear a pollen mask.
- Take a vacation during the height of pollen season to a more pollen-free area such as the beach.
- Keep your car windows closed when driving.
- Don’t grow too many, or over water, indoor plants.
- Minimize early morning activity — between 5-10 a.m. — when pollen is usually emitted.
- Don’t hang sheets or clothing out to dry. Pollens and molds may collect in them.
Why do people suffer from allergic rhinitis or hay fever?
Allergic rhinitis, which is often called hay fever, is the body’s immune system overreacting when it comes into contact with certain allergens such as pollen or mold. When people with allergies inhale these substances, an allergic antibody dubbed IgE treats them like dangerous invaders and gloms onto them. This triggers the release of histamines and other chemicals, which cause the trademark allergic response of sneezing, dripping nose, congestion and itchiness.
What are common symptoms?
- Watery eyes
- A runny nose
- Itchy eyes and nose
- In children, dark circles under the eyes
How can you distinguish between hay fever and the common cold?
While watery eyes, sneezing, runny nose and itchy eyes and nose are common to both, a cold can also cause fever and aches and pains. And allergic symptoms last as long as you are exposed to the allergen and beyond, while a cold should clear up within several days to a week.
How many people suffer from hay fever?
At least 35 million people in the United States have seasonal allergic rhinitis.
What is an allergen?
Any substance, such as pollen, mold or animal dander, that can trigger an allergic response.
What is pollen?
Pollens are the microscopic, egg-shaped male cells of flowering plants that are necessary for plant fertilization.
Pollens from plants with bright flowers, such as roses, usually do not trigger allergies. But many trees, grasses and low-growing weeds have small, light, dry pollens that are well-suited for dissemination by wind currents. These are the pollens that trigger allergy symptoms.
How do you test for allergies?
To determine which specific substances are triggering your allergies, your allergist will test your skin, or sometimes your blood, using tiny amounts of commonly troublesome allergens. There are several types of tests:
Scratch or puncture tests in which a tiny amount of allergen is scratched across or lightly pricked into the skin. If you have an allergy, the specific substances that you are allergic to will cause an allergic reaction in your body that culminates in redness and swelling.
Swelling will occur only in the spot where an allergen to which you are allergic is scratched onto your skin. Thus, if you are allergic to ragweed pollen but not to cats, only the spot where the ragweed allergen is scratched onto your skin will swell and itch.
Intradermal test, a modified, slightly more sensitive version of the scratch or puncture test that involves injecting a tiny amount of allergen under the skin, usually on the upper arms. Your allergist may do this test when your reaction to the scratch test cannot be clearly determined.
The RAST, or radioallergosorben, test involves drawing blood, it costs more, and the results are not available as rapidly as skin tests. RAST tests are generally used only in cases in which skin tests can not be performed, such as on patients taking certain medications or those with skin conditions that may interfere with skin testing.
What medications are used to treat allergies?
Antihistamines are used to prevent or relieve the symptoms of allergic rhinitis and other allergies. They work by preventing the production of histamine, a substance produced by the body during an allergic reaction.
Decongestants are used to treat nasal congestion and other symptoms associated with colds and allergies. They work by narrowing blood vessels, leading to the clearing of nasal congestion. Steroid nasal sprays reduce nasal inflammation and the accompanying congestion, sneezing and runny nose.
What is immunotherapy?
Treatment may include immunotherapy, better known as allergy shots, which work by desensitizing the immune system to a specific allergen through periodic injections of the offending substance in gradually increasing amounts. Injections, which are usually given monthly for up to five years, typically begin to take effect within three to six months. Immunotherapy is ultimately successful in up to 90 percent of patients with seasonal allergic rhinitis and up to 80 percent with perennial allergic rhinitis.
What’s the link between allergies and asthma?
So-called allergic asthma accounts for about 60 percent of all asthma cases. It is triggered, not surprisingly, by an allergen — be it pollen, dust, mold or animal dander. When an allergic person is exposed to an allergen, a series of reactions is set off.
First, antibodies in the immune system whose purpose is to capture unwanted invaders are produced. These antibodies, dubbed IgE, journey through the bloodstream and lock onto the surface of so-called mast cells, plentiful in the nose, eyes, lungs and gastrointestinal tract. Then they lie silently in wait until the allergen strikes again. The IgE antibodies, now poised, jump on and gobble up the allergens, triggering the release of inflammatory chemicals such as histamine and prostaglandin.
The airways become inflamed, boggy and red — very much like the skin of an eczema patient. This, in turn, causes the airways to narrow, or bronchospasm. The victim begins to wheeze, cough, even lose his breath.
What is the major risk factor for hay fever?
A family history of allergies is the single most important factor that predisposes a person to develop allergic disease. If one parent has allergic disease, the child has a 48 percent chance of developing allergies; the risk grows to 70 percent if both parents have allergies.
Can breast-feeding reduce risk?
Some research studies have found that breast-feeding from birth to age 1 can help protect a child from potentially developing allergies or asthma.
Can weather influence hay fever symptoms?
Allergy symptoms are often minimal on days that are rainy, cloudy or windless, because pollen does not move about during these conditions. Hot, dry and windy weather signals greater pollen and mold distribution and thus, increased allergy symptoms.
What about locale?
If you are allergic to plants in your area, you may believe that moving to another area of the country with different plants will help to lessen your symptoms. However, many pollens, especially grasses, and molds are common to most plant zones in the United States. Additionally, other related plants can also trigger the same symptoms.
As a result, many who move to a new region to escape their allergies find that they acquire allergies to new airborne allergens prevalent in their area within one to two years. Therefore, moving to another part of the country to escape allergies is often ultimately disappointing, and not recommended.
SOURCES: American Academy of Allergy, Asthma and Immunology and MSNBC research.