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Amber Waves of...ah...ah...achoo! What you need to know about allergies

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Spring has sprung, the sun is shining, flowers are beginning to bloom and pollen is in the air. Often thought of as a bright and cheerful time, for many people spring is a season when their heads feel like over-ripe melons, their eyes water and the tissue industry is kept in business. Many people feel they may have a perpetual cold that never seems to dissipate and that only gets worse in the spring. It seems like a minor irritation, not worth their time to complain about—but instead of a cold, they may be suffering from an allergic reaction.

It is very rare that people talk about their allergies, and some people I have spoken with seem unwilling to admit that seasonal allergies may be the cause of their discomfort. Given that over half of Americans test positive for one or more of the 10 most common allergens, having an allergy or two should be considered normal, not a reason for shame.

10 most common allergens:


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  • Alternaria mold

  • Bermuda grass

  • Cat

  • German cockroach

  • House dust mite

  • Peanut

  • Ragweed 

  • Russian thistle

  • Rye grass

  • White oak

So what are allergies? Allergies are reactions that occur when a person’s immune system responds by attacking normal, everyday substances when they enter the body. A shift in the wind bringing pollen, or visiting a friend who owns a cat, can cause symptoms such as swelling, itchiness, rashes, watering eyes, sneezing, feeling warm, nasal congestion (aka hay fever), trouble breathing, and activity-induced nausea. Airborne allergens can also trigger asthma attacks, caused by chronic inflammation of the airways; the inflammation can be so severe that airways swell shut.

Allergy myths:

If the symptoms are ignored the allergies will go away. Everyone who has allergies can sadly attest that this is just not possible; we wish it were. Since allergies are an immune-system response to a substance, ignoring the symptoms will not make them go away. With continued exposure, people are likely to see an increase in symptoms. This would exhaust their body and weaken their immune system, and may even increase their chances of catching a cold.

It’s all in people’s heads. When people have an allergic reaction, chemicals such as histamine are released to attack the invading allergens. Allergies are a measurable chemical reaction, not a flight of fancy. Having to avoid allergens can mean skipping certain activities, being unable to visit people with pets or forgoing a favorite food. Avoiding things is not fun. Making fun of people because of their allergies is just plain cruel and should be avoided at all costs.

If I take some allergy medicine, it doesn’t matter how much I am exposed. Allergy medication is not a pass for people to expose themselves to allergens as much as possible. Medications only decrease the chances of a severe reaction. If people overexpose themselves, then their medication may not be able to compensate (see below).

Did you know?

Hair is a giant trap for allergens and smog. A quick and easy way for people to cut down on the allergens they are exposed to is to wash their hair and change their clothes immediately when they arrive home.

Allergic reactions are additive. People with multiple allergies will have an increase in allergic reactions when exposed to more than one allergy at a time. Each allergen can be thought of as a bag of money being piled on a scale: the more the bags that are added, the more the scale dips and the worse people’s reactions will be. This is one reason why avoiding known allergens is so important. Less allergen exposure decreases the risk of anaphylactic shock, the most severe form of allergic reaction.

Anaphylactic shock is a life-threatening allergic reaction that causes restriction of the airways and other symptoms. It can completely close the airways, causing death. If you suspect someone may be experiencing anaphylactic shock, immediately call 911 and follow the operator's instructions until help arrives. Ongoing treatment of allergies does not provide complete protection against this condition. Preventing exposure, especially to multiple allergens, is the best way to avoid it.

Visiting your doctor:

  • List all symptoms and any discomfort, including but not limited to heartburn, swelling, trouble breathing, itchiness, watering eyes, sneezing, feeling unusually warm, activity-induced nausea, swelling and any other physical symptoms. There is no such thing as too much information when it comes to speaking with a doctor about medical symptoms.

  • Ask the doctor questions about why he or she diagnosed a specific allergy or an alternative cause of symptoms. Also ask what can do to minimize or prevent symptoms.

  • Write down the doctor's comments and instructions so that none are forgotten and no vital information is mixed up.

  • Bring a relative you trust to help take notes and ask questions.

Most important, be honest and open with your doctor—and follow the doctor’s advice!

Support for people with allergies is available through the Allergy and Asthma Foundation of America.

Allergies are a common and serious health issue. With the guidance of a trained physician and the use of medication and lifestyle changes, it is possible to lead a health, happy and relatively symptom-free life.

MeSH Cloud for Allergies (270,927 PubMed Articles) by Lieger Cat:

References and additional resources:

U.S. National Library of Medicine. 2011. Talking With Your Doctor. Medline Plus.

Baxi, S. N. and Phipatanakul, W. 2010. The Role of Allergen Exposure and Avoidance in Asthma. Adolesc Med State Art Rev. 21(1): 57–ix.

Mayo Clinic Staff. 2010. Hay Fever Treatment and Drugs.

Grammatikos, A.P. 2008. The genetic and environmental basis of atopic diseases. Ann. Med. 40 (7): 482–95.

Sarkar IN, Schenk R, Miller H, Norton CN. 2009. LigerCat: using “MeSH Clouds” from journal, article, or gene citations to facilitate the identification of relevant biomedical literature. AMIA Annu Symp Proc. Nov 14, 2009:563-7.

Image credits: "Allergens? Who, me?" (cat), Stephanie Phillips, Copyright 2005, used with permission; "Histamines v. Pollen: A Dramatic Reenactment," Jeffrey D. Deards, jdeards@verizon.net, Copyright 2011, used with permission; amber waves of grain, Creative Commons by Attribution 2.0 Generic, Ben Fredericson (xjrlokix).

About the author: Kiyomi Deards is an Assistant Professor with the University of Nebraska-LIncoln University Libraries. She is the librarian for chemistry, biochemistry, biological sciences and the Cedar Point Biological Station, and the incoming physics librarian. Ms. Deards belongs to several professional organizations focused on libraries, education, science and technology. She currently manges the website of the Association of College and Research Libraries Residency Interest Group. Her research and educational interests are in STEM education and career issues, diversity, library management, mentoring, and teaching. She maintains a personal blog and website, LibraryAdventures.com.

The views expressed are those of the author and are not necessarily those of Scientific American.