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Severe Allergy: Symptoms & Treatments

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  • Mild vs Severe Allergies

    Mild vs Severe Allergies

    Allergies can affect people differently. While one person might have a mild reaction to a certain allergen, someone else might experience more severe symptoms. Mild allergies are an inconvenience, but severe allergies can be life-threatening.

    Mild allergy symptoms may not be extreme, but they can affect the entire body. Mild symptoms include skin rash, hives, runny nose, itchy eyes, nausea, or stomach cramping.

    Severe allergy symptoms are more extreme. Swelling caused by the allergic reaction can spread to the throat and lungs, causing allergenic asthma or a serious condition known as anaphylaxis.

  • Severe Allergens

    Severe Allergens

    The substances that cause allergies are called allergens. Although pollen, dust mites, and mold spores are common allergens, it is rare for a person to have a severe allergy to them, since they are everywhere in the environment. Possible severe allergens include pet dander, insect stings, certain medicines such as penicillin, and food. The foods that cause most allergic reactions are peanuts, tree nuts, fish, shellfish, eggs, milk, wheat, and soy.

  • Allergies that Last a Lifetime

    Allergies that Last a Lifetime

    Some allergies can grow less severe as a child grows up. This is particularly true for egg allergy.  However, most allergies last throughout life.

    You can also develop allergies as a result of repeated exposure to a toxin, such as bee stings or poison oak.  With enough cumulative exposures over a lifetime, your immune system can become hypersensitive to the toxin, giving you a severe allergy.

  • The Immune System

    The Immune System

    Allergy symptoms occur when your immune system overreacts to allergens in your body. Your immune system mistakenly believes that an allergen from a food, such as a peanut, is a harmful substance invading your body. The immune system releases chemicals, including histamine, to fight off the foreign invader.

    When your immune system releases these chemicals, it causes your body to have an allergic reaction.

  • Swelling & Breathing Difficulties

    Swelling & Breathing Difficulties

    When the immune system overreacts, it can cause body parts to swell, particularly the lips, tongue, fingers, and toes. If your lips and tongue swell too much, they can block your mouth and prevent you from speaking or breathing easily.

    If your throat also swells, it can cause trouble swallowing or breathing. Your airways can also swell, causing shortness of breath, wheezing, or even asthma. Antihistamines and steroids can help bring the allergic reaction back under control.

  • Allergenic Asthma

    Allergenic Asthma

    Asthma occurs when the tiny structures in your lungs become inflamed, causing them to swell and restrict airflow. Since allergic reactions often cause swelling, they can trigger a form of asthma called allergenic asthma.

    Allergenic asthma can be treated the same way as regular asthma: with a “rescue” inhaler, such as albuterol. Albuterol makes your airways expand, allowing more air to flow into your lungs. However, inhalers aren’t effective in cases of anaphylaxis, because anaphylaxis closes off the throat, preventing the medication from reaching the lungs.

  • Anaphylaxis


    Anaphylaxis occurs when the allergic swelling gets so extreme that it causes your throat to close, preventing air from getting through. In anaphylaxis your blood pressure can drop, and your pulse can become weak or thready. If the swelling restricts airflow for long enough, you can even fall unconscious.

    If you think you’re starting to experience anaphylaxis, use an epinephrine (adrenaline) injector, such as EpiPen, Auvi-Q, or Adrenaclick. Epinephrine helps to open your airways, allowing you to breathe again.

  • Get Diagnosed & Be Prepared

    Get Diagnosed & Be Prepared

    If you have severe allergies, an allergist can evaluate your condition and help you manage your symptoms. An allergist can run a series of tests to find out what you’re allergic to. They can give you an epinephrine injector to carry with you in case of anaphylaxis. You can also work with an allergist to develop an anaphylaxis emergency care plan, which can help you track your symptoms and medication.

    You may also want an emergency medical bracelet, which can help inform emergency health workers of your condition.



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  • Food Allergen Labeling And Consumer Protection Act of 2004 Questions and Answers.  (2006, July 18).  U.S. Food and Drug Administration.  Retrieved November 14, 2013 from
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  • Treatment & Managing Reactions. (n.d.). Food Allergy Research & Education. Retrieved November 19, 2013 from