|Ragweeds are a genus of flowering plants, Ambrosia, in the aster family. With dozens of species scattered all across the U.S., its pollen produces some of the most severe and widespread allergies every year.
Ragweeds are annuals, most commonly found in the eastern and Midwestern states of the U.S. And though ragweeds only live for one season, in that season each plant can produce up to 1 billion pollen grains. Ragweed pollen is generally at its heaviest after midsummer. The flowers generally mature by this time and begin releasing their pollen. Warmth, humidity and breezes after sunrise help the release. With pollen being so light and easily airborne, breezes can quickly and easily scatter ragweed pollen, under the right conditions, up to hundreds of miles. As it travels, the pollen fertilizes other ragweed plants for the following year's crop.
In general, ragweed plants prefer drier areas, sunny grassy plains, sandy soils, river banks, and roadsides, though you can find ragweeds growing nearly anywhere. Worldwide, there are 41 different species of ragweed that live in varying climates, from the more temperate regions found in the eastern half of the United States to drier, more desert-like locales.
Ragweed allergy, like nearly all other allergies, is the overreaction of the body's immune system to what is essentially a harmless substance. In the case of people with allergies, the human immune system is treating ragweed pollen as a harmful substance instead of ignoring it. In an effort to rid the body of this mistakenly harmful pollen, the body produces a variety of reactions which we commonly refer to as hay fever. Most often symptoms arise after inhaling ragweed's light, airborne pollen, though there are a few insects that cross pollinate ragweed, and contact with them can also cause an allergic reaction. While not limited to just ragweed, allergic reactions can be caused by other pollinating plants in the same Family as ragweed (sage, groundsel bush, mugworts, burweed marsh elder, etc.).
Nearly 75% of all people who are allergic to pollen-producing plants will also be allergic to ragweed. So in general, if your body reacts to ragweed pollen, it is more than likely to also react to other pollens. People with ragweed allergy may also get symptoms when they eat cantaloupe, watermelon, or banana. This link between certain foods' relationship to seasonal allergies is referred to as allergen "cross-reactivity". Chamomile tea, sunflower seeds and honey containing pollen from Compositae family members can occasionally cause severe reactions, including shock.
Even if you are not allergic to ragweed, you've most likely heard of the symptoms and have come across many people who struggle with them during the late summer and fall months. More commonly referred to as hay fever, the symptoms range from mild irritation, runny nose, puffy eyes, stuffy nose and sneezing to inflamed sinuses and a sore throat. More severe allergy sufferers may exhibit these symptoms as well more severe reactions like asthma attack, sinusitis, headaches, and insomnia.
Currently, the most common testing method is a skin sensitivity test. After a standard exam and review of your medical history, this simple test can test your body's reaction to a variety of allergens, including ragweed.
For this test, the skin is scratched or pricked with extract of ragweed pollen. In sensitive people, the site will turn red, swollen and itchy. Sometimes blood tests are used to see if an antibody to ragweed is present. Though sometimes necessary, this takes longer for processing by a laboratory, and it is more expensive. In all, proper diagnosis relies upon a combination of information from multiple sources.
There is no cure for ragweed allergy, and eliminating ragweed is essentially impossible. As with most allergies, the best control is to avoid contact with the pollen. This is difficult given the amount of ragweed pollen in the air during pollination time, its proliferation across the globe, and the ease of dispersal. However, by taking control of your indoor environment and limiting your exposure, you drastically reduce your reaction to ragweed pollen.