post-title End of Summer, Early Fall Allergies: Weed Allergy 2012-08-29 14:52:04 yes no Posted by

End of Summer, Early Fall Allergies: Weed Allergy

By Midwest Allergy Physician Jennifer Z. Bullock, M.D., F.A.A.A.A.I., F.A.C.A.A.I., F.A.A.P. Summer is winding down, school has started, and we are heading into Fall. The nose, chest or eye symptoms that you or your child might be experiencing around this time of year could be due to weed pollen allergy. There are a number of weeds […]

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By Midwest Allergy Physician Jennifer Z. Bullock, M.D., F.A.A.A.A.I., F.A.C.A.A.I., F.A.A.P.

Summer is winding down, school has started, and we are heading into Fall. The nose, chest or eye symptoms that you or your child might be experiencing around this
time of year could be due to weed pollen allergy. There are a number of weeds that produce airborn pollens from mid-August through September: Ragweed, English Plantain, Cocklebur, Nettle, Lambs Quarter, and Wormwood, to name a few. By far, Ragweed is the most potent and allergenic of the weeds, and it is probably the major cause of allergy symptoms during this time of year, although people who are allergic
to multiple different weeds may have more severe symptoms.

What is Ragweed?

The two most common species of Ragweed are “Giant” Ragweed which may grow to be 6-8 feet tall, and “Short” Ragweed, which usually grows to be 2-3 feet tall. Ragweed grows in abandoned lots, any fields not treated with herbacides, along highways, and along riverbanks. It grows so quickly and so well that it can grow through the cracks in pavement and sidewalks. Some species of Ragweed produce very small greenish-yellow buds that release pollen into the air. Goldenrod is a plant that produces large yellow flowers that bloom during the weed season, and it is often found growing right next to Ragweed. It is often mistakenly thought to be the major plant to cause allergy symptoms during this time of year. Flowering plants, such as Goldenrod do not reproduce by releasing their pollen into the air, and are therfore not a major cause of hayfever. Their pollen is heavy and sticky, and rather than becoming airborn, it is spread by insects such as bees, butterflies, and ants.





When does Ragweed season start and end?

Ragweed is “programmed” to pollenate when the sun starts to shine on the plant at a very specific angle in the midday. Hence, in the Midwest, Ragweed pollen season usually starts, like clockwork, every year, on or around August 15 th. From start to finish, Ragweed releases its pollen for about 6 weeks. Ragweed pollen is most abundantly found in the air around the last week of August, and the first two weeks of September. The season peaks around Labor Day weekend. Many people find that they have symptoms around this time of year, and their symptoms then start to improve toward the end of September. Symptoms that continue into mid-October and through November are due probably more to “leaf” mold, or mold spore season. Although you might not see Ragweed in your yard or neighborhood, you can be affected by its pollen. Ragweed pollens can float and travel in the air for hundreds of miles, so most people living in our region of the country have exposure to it. Dry and windy weather may make pollen allergy worse, whereas rain can “wash” pollen out of the air for a short period of time, offering some relief for allergy sufferers.

Ragweed Pollen

Ragweed pollen magnified. The “spines” on the outside of Ragweed pollen help it to stay buoyant and then stick to surfaces, which unfortunately includes people’s eyes, nose and lungs.

What symptoms does Ragweed allergy cause?

There are many different symptoms that can occur from weed pollen allergy: runny nose, itchy nose, nosebleeds, itchy throat and ears, sneezing, nasal congestion, itchy, puffy, watery eyes, dark circles under the eyes, cough, headaches, sinus infections, ear infections or ear pressure, asthma attacks, and fatigue, poor sleep or snoring. New research shows that toward the end of the Ragweed season, the pollens may split or “fraction” into smaller pieces. These smaller pieces are more likely to penetrate the lower airways of the lungs and cause asthma or cough.

How can I tell the difference between allergy and a cold?

The weed pollen season occurs at a time when children, teachers, and school employees or administrators are going back to school. This is also a common time for people to have upper respiratory infections (colds). This often makes it difficult to determine whether symptoms are due to Ragweed allergy or a cold. A cold typically lasts for 7 to 10 days and may start with sneezing, a fever, or malaise (a general feeling of discomfort.) Nasal congestion and runny nose then develop, symptoms worsen over a couple of days, then improve. Often, other people in the family will also get sick. Weed pollen allergy is more likely to last for closer to 3 (or more) weeks, and does not involve fever or malaise. If a person experiences symptoms around this time of year, every year, that also makes weed allergy a good possibility.

Can Ragweed allergy cause food allergies?

Some people with Ragweed allergy can experience almost immediate discomfort of the mouth upon eating uncooked fruits and vegetables that are related to Ragweed. This is called oral allergy syndrome or pollen-food syndrome. Certain fruits and vegetables are related to ragweed, and share similar proteins with Ragweed: cantaloupe, honeydew melon, watermelon, banana, cucumber, green pepper, sunflower seeds, and squashes, especially zucchini. This occurs most commonly with the melons, however. Because the immune system recognizes Ragweed as an allergen, it also recognizes these uncooked foods as “Ragweed,” and this causes histamine release in the mouth and sometimes throat, resulting in itchy mouth, itchy throat, burning of the mouth or throat, or mild itchy nose or congestion. Usually, this causes an uncomfortable feeling for a short period of time and is not life-threatening.  Only very rarely does the problem become more severe to involve swelling of the mouth or throat, abdominal cramps, diarrhea or vomiting. If the fruits or vegetables are canned or cooked, this processing “denatures” or changes their protein structure enough that they no longer are recognized by the immune system, and there is
typically no reaction. Oral allergy syndrome may be a problem all year around, but sometimes it occurs only during Ragweed season. It is not well understood why some patients with Ragweed allergy develop this and others do not. Avoidance of the offending foods, especially during Ragweed season, is usually recommended.

How can I avoid Ragweed exposure and feel better in Ragweed season?

Pollens are difficult to avoid, and it doesn’t take much exposure to have symptoms. Many people get enough outdoor pollen exposure during normal daily activities to have symptoms. Symptoms can be worse the more time you spend outside, so limiting outdoor activity, if possible, can help. Pollination may be more heavy from 5am to 10am, so limiting activity during this time of day can also help. It is tempting to keep windows and doors open as temperatures cool off this time of year, but keeping things closed up will help. Taking antihistamines, prescription nose sprays, and eye drops daily will help to keep things under control. There are very good oral antihistamines and eye drops widely available over the counter, so people often prefer to start with these. Starting these medications early in August, before the weed season gets under way, will often help to keep things under better control, and help you stay ahead of the game. If you think you may need more than over the counter remedies, consult your primary care doctor or our office for an appointment.

When should I consider taking allergy shots for my weed allergy?

Allergy immunotherapy or allergy shots are a good option for anyone who does not have improvement with medications, for anyone who can’t tolerate allergy medications, or for people who find that they have to take medications for a good portion of the year to control allergy symptoms, especially when asthma or sinus infections are a problem. Some people want more of a definitive treatment directed at the underlying allergies, and allergy shots can provide this by helping your body to become “immunized against” or “tolerant to” allergens. Do not hesitate to contact our office if you would like to have more information about allergy shots.

Picture Sources:
Goldenrod: Better Homes and Gardens Internet Plant Finder
Ragweed: Sudkamp, Scott, Missouri Department of Conservation. “Quail-Friendly
Plants of the Midwest.”
Ragweed pollen: Castleman, Michael, March/April 2006. “Stop the Seasons Sneezin.”

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