Why Can’t I Breathe?

Environmental allergies are one of many ways allergies can inhibit our day-to-day lives. (http://www.allergydruginfo.com/images/allergy-medication.jpg)

Whether it is a runny nose, itchy eyes, or a skin rash, many of us have faced the systems of an allergic reaction at some point in our lives. They are a determining factor in the places we go, the pets we have, and even the food we eat. The Asthma and Allergy Foundation estimates that allergies affect 50 million Americans, making it the fifth leading chronic disease in the country. Despite the frequency of allergies in the population, few individuals really understand how allergies occur (1).

A healthy body’s immune system is set up to constantly identify invading pathogens by identification of self vs. non-self. While one definitely should not be upset that the body has this skill, things can become problematic when the body cannot differentiate what non-self entities are harmful or harmless. Allergies are induced when the body begins to strike against non-harmful entities (5).

The above picture describes the process of eliciting an allergic response. An allergen causes B cells to release IgE, which bonds to Mast cells or Basophils. When allergens interact with these antibodies, the cells they are attached to lyse and release chemicals that cause allergy symptoms. (http://microbiology2009.wikispaces.com/Histamines--What+They+Do+%26+What+Anti-Histamines+Do+to+Stop+Them)

When an allergy is induced, the body identifies an allergen, inducer of the allergic response, as an invader. An allergen may be anything individuals are exposed to in day to day life (2). In order to remove this invader, the body elicits a response to destroy it. T-cells and B-cells, two types of White Blood Cells, play an important role in eliciting this response. When these cells are presented with a foreign substance, T-cells either recruit more White Blood Cells or directly attack whatever invader is present. B-cells release antibodies, which are also engineered to fight off the specific invader. IgE is the antibody specifically associated with allergic reactions. It bonds to basophils and mast cells, eventually causing them to release their contents, including a protein named histamine (5).

Histamine influences the body by causing inflammation. When an area of the body is inflamed, blood vessels become less dense, allowing an increase in the number of blood cells able to enter the site of histamine release. This increase in blood cells causes swelling at the site of the allergic reaction (4). These additional blood cells may also trigger the allergic response, causing the reaction to become worse with continued exposure. Histamine also causes smooth muscle to contract (6), which leads to breathing difficulties frequently associated with an allergic reaction.

There are several ways a person may try to deal with allergies. Some simply try to avoid allergens that tend to cause an immune response. Sometimes, allergens cannot be avoided, so allergy treatment drugs are provided. One common way to treat allergies is to use anti-histamines, such as Claritin and Allegra. They work to inhibit the ability of histamine to bond with other molecules that cause the allergic response (4). In severe allergic reactions, some individuals require an epinephrine injection. Epinephrine causes blood vessels to contract, inhibiting the allergic response (3). In severe cases, immunotherapy may be used. Immunotherapy forces the patient to be exposed to the allergen that normally elicits a response. While it is not always effective, in some cases it causes the body to release IgG, a blocking antibody that improves a subject’s response to an allergen (5).

While some of these ways of dealing with allergies are achieving a reasonable amount of success with sufferers, a larger question remains. How do we prevent allergies from developing in the first place? Research from the University of Copenhagen claims allergies tend to develop more prevalently in individuals who are not exposed to many types of bacteria in the first six months of life (7). This is why infants born via cesarean section have a much higher tendency to develop allergies than those born naturally (7). Naturally born children are much more heavily exposed to the mother’s bacteria in the birthing process. Some researchers suggest this reasoning is also why children raised in rural environments are less prone to develop allergies.

Though we still have a lot that we may learn about allergies, the information we see indicates that an increase in allergies is being caused by modern medicine. By not allowing bacterial exposure early in life, we are forced to face alternate medical consequences. Hopefully, researchers will develop a fuller idea of how to prevent both illness and allergies, but, in the meantime, we are left to take our Claritin, fear our bees, and exhibit caution in the presence of peanuts.

Works Cited

1. “Allergies – PubMed Health.” Web. 09 Nov. 2011. <http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001815/>.

2. Cunha, John P. “Allergic Reaction Symptoms, Causes, Signs, Treatment and Prevention by EMedicineHealth.com.” EMedicine Health. Web. 09 Nov. 2011. <http://www.emedicinehealth.com/allergic_reaction/article_em.htm>.

3. “Epinephrine Injection: MedlinePlus Drug Information.” National Library of Medicine – National Institutes of Health. Web. 09 Nov. 2011. <http://www.nlm.nih.gov/medlineplus/druginfo/meds/a603002.html>.

4. “Histamine.” Biology @ Davidson. Web. 09 Nov. 2011. <http://www.bio.davidson.edu/courses/immunology/Students/spring2000/lamar/mfirp.htm>.

5. “HowStuffWorks “How Allergies Work”” HowStuffWorks “Science” Web. 09 Nov. 2011. <http://science.howstuffworks.com/environmental/life/human-biology/allergy.htm>.

6. Schmidt D, Ruehlmann E, Branscheid D, Magnussen H, Rabe KF.  1999 Aug.  Passive sensitization of human airways increases responsiveness to leukotriene C4.  European Respiratory Journal 14(2): 315-319.

7. Hans Bisgaard, Nan Li, Klaus Bonnelykke, Bo Lund Krogsgaard Chawes, Thomas Skov, Georg Paludan-Müller, Jakob Stokholm, Birgitte Smith, Karen Angeliki Krogfelt. 2011. Reduced diversity of the intestinal microbiota during infancy is associated with increased risk of allergic disease at school age. Journal of Allergy and Clinical Immunology 128 (3): 646 -652.

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About bryanedwards

Hello everyone! My name is Bryan Edwards. I am a senior at DePauw University preparing to complete my major in questioning things. Okay...that may not be what my paperwork will say, but it has been true of my college experience. I am a double major in biology and philosophy. Though these two field may feel worlds apart at times, they are simply different ways of evaluating claims about the world around us in hopes of finding real truth. This desire to find truth has only been further developed by my experience in the Science Research Fellows program. This program has provided me experience critically evaluating current research, as well as designing and directing research to answer questions of my own. Whether I am working with deductive arguments, behavioral assays, or an ELISA test - I'm out to get to the bottom of things. I plan to utilize this zest for problem solving as a physician. Critical questioning and problem solving will be key in cracking complicated diagnoses as well as resolving complex ethical dilemas. I'm glad you've chose to join me on this quest for understanding and hope you'll continue to explore with me through the remainder of Common Sense Science!

3 thoughts on “Why Can’t I Breathe?

  1. I had a friend in the 5th grade that was terribly allergic to dogs and cats. He had pretty bad asthma along with his allergies. For him to come visit my house we had to keep the dog and cat as far away from him as possible and do some quick vacuuming. I always felt sorry for him because I absolutely loved my pets and he would never get to play with them! A few years ago he surprised me by showing up at my house after many years of not seeing him. I asked if I needed to run in real quick and do a quick clean up of the house. To my amazement he said the allergies did not really affect him anymore and the dog could even be in the house! What had happened that changed this kids intense allergies to something of the past?
    When I first read this post that was one of the first things that came to my mind. I did a little bit of research and found out that allergies can actually develop and or disappear over time. I listened to a pod cast produced by the HealthTalk webcast with special guest Dr. Pramod Kelker, a practicing allergist and the founder of the National Cough Clinic and chair of the Metro Asthma Coalition who explained that children as well as adults can develop allergies. Allergies can actually start at any point in your life.
    Dr. Kelker also explained that having allergies does run in the family. If your parents have allergies then you are more likely to have allergies. The interesting fact about this is it does not matter what your parents are allergic to, you will just be more likely to be allergic to something (ie your mom could be allergic to dogs and you could be allergic to pollen).
    The fact that allergens can be developed and disappear at various stages in life is sort of an end of the road conclusion. Science does not have set research verifying how or why this occurs. They believe right now that if you already have the genetic disposition for allergies then when you develop them depends on environmental changes over your lifetime. When someone develops an allergy most of the time they need to have been exposed to the allergen at least 2 times prior. In respect to an allergy disappearing, when you are a child with a milk or egg allergy it more than likely will disappear as the child grows, but a peanut allergy will more than likely never disappear. The same can be said with environmental allergies in that they are normally present for a lifetime. Dr. Kelkar ended with explaining that as of now he cannot recommend steps to help decrease the intensity of your allergy or make it disappear all together. However he is hopeful that based on the type of research currently being conducted we will have an answer to these questions in the near future.
    Going back to my friend’s case, it is more likely that he had not completely gotten rid of the pet allergy, but that it actually just decreased in intensity enough for him to handle homes with dogs. Last time I checked he still did not own a dog himself, which can help explain his environmental situation. It might even be that he is just unaware that he still has the allergy. Allergies are pretty common in today’s life. It’s nice to think we could one day just “grow out of them”. : )

    PodCast Growing into and Out of Allergies, 2008 http://www.everydayhealth.com/asthma/webcasts/growing-into-and-out-of-allergies-transcript-1.aspx

    The American Academy of Allergy, Asthma, and Immunology. http://www.aaaai.org/home.aspx

  2. I thought that this article was really interesting as a suffered of allergies and asthma myself. I was interested in learning more about the immunotherapy as it was something that I had heard of but never looked into. I found it interesting that it only worked on certain allergies, but did not work on food allergies or hives. After researching the treatments options, it is obvious why it is only suggested for those with severe allergies. The shots with increasing amount of the allergen happen once or twice a week for the first several months and then every 2-4 weeks for 2-5 years. For each shot, you need to stay and be monitored for at least half an hour afterwards and you cannot participate in vigorous activity for 2 hours before or after. I know for me that treatment plan would make it seem much more reasonable to just deal with my allergies rather than go through this to try and get rid of them.

    http://www.webmd.com/allergies/guide/shots

  3. This article interested me because I have struggled with allergies my whole life. When I was younger I would just take over the counter medicine and deal with the sneezing, itchy eyes and nose, and post-nasal drip. However, in high school I developed a deep cough that would not go away and would cause my entire body to contract. After multiple months of this cough, I was diagnosed with extrinsic (allergy-related) asthma. This was kept under control by my asthma medicine and prescription allergy medicine as long as I chose to stay away from nature (I’m allergic to mold, trees, weeds, grasses, and dust mites). However, about half the time running outside with my high school gym class would cause me to wheeze or even have a full-blown asthma attack. During college I began working outside and would break into rashes when I did research in the nature park. After this, I went to an allergist to see what could be done.

    One solution they offered to me was immunotherapy, which Catie mentioned above. I find it interesting that when I look up immunotherapy there are articles stating that it may not be as effective as people believe it to be. I have had immunotherapy weekly for the past 2.5 years; it was one of the best decisions of my life. I cut down my asthma medicine to less than half the dosage I previously needed and now only take it once a day instead of twice. Most of the year I do not need allergy medicine (fall being the exception due to the large amount of mold floating around). Although it may be extreme, immunotherapy allowed me to be in control of my allergies and, consequently, my asthma. Below is a link to a site that describes extrinsic asthma and another that evaluates the effectiveness of immunotherapy.

    http://www.everydayhealth.com/asthma/allergic-asthma.aspx
    http://171.66.122.149/content/151/4/969.abstract

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