The Truth about Allergies and Your Immune System
Here's a primer that tells you about allergies, your immune system, what happens in the body and what symptoms are dangerous.

powered by healthline

Average Ratings

The Truth about Allergies and Your Immune System

If you are one of the millions of Americans who suffer from allergies, no one has to tell you how miserable they can make you feel. An allergic reaction happens when your body's immune system mistakes a harmless substance as a foreign intruder. In response, the immune system produces antibodies.

Certain cells then release chemicals such as histamine. Those chemicals are responsible for allergy symptoms, such as sneezing, watery eyes, runny nose, wheezing and cough.

Most people who are prone to allergies, as well as related conditions like asthma and eczema, can thank their families. If your parents or other relatives have allergies, you are more likely to have them, too. But just because it runs in your family doesn't mean you will definitely get allergies. You need to be exposed to an allergen and become sensitive to it. Then you have developed an allergy. Most allergies start in childhood, but you can also get a new allergy as an adult.

Common allergens include:

  • Pollen
  • Certain foods
  • Mold
  • Dust mites
  • Pets
  • Cockroaches
  • Cigarette smoke
  • Medications
  • Insect stings
  • Latex

Allergies and asthma
Allergies and asthma often coexist. Asthma causes wheezing, tightness in the chest, shortness of breath and coughing. You are more likely to have asthma if someone in your family also has it. Asthma can be triggered by allergens.

Are allergies dangerous?
Most of the time, as bad as you might feel, allergies are not dangerous. The exception is anaphylaxis, which is a severe life-threatening allergic reaction.

What is anaphylaxis?
Anaphylaxis is an often sudden reaction to an allergen that requires IMMEDIATE medical treatment. The leading culprit is food allergies, especially allergies to peanuts and tree nuts. Penicillin, insect stings and latex can also cause anaphylaxis in someone who is allergic. Symptoms may occur in various combinations and throughout the body. They include:

  • Difficulty breathing, wheezing, coughing, chest pain
  • Trouble swallowing, swelling of the tongue and throat
  • Dizziness or fainting
  • Itching, hives or redness of the skin
  • Weak pulse, shock
  • Vomiting, diarrhea, cramps
  • Itchy mouth, sneezing, runny nose

What can you do to treat anaphylaxis?
If you have symptoms of anaphylaxis or think someone else is having symptoms, call 911 immediately. Anaphylaxis is life-threatening. The best immediate treatment is an injection of the medicine epinephrine. People who have allergies may be prescribed an auto-injecting device to use in case of serious allergic reaction. The medicine acts to increase the heart rate, open the airways and constrict the blood vessels. Further treatment at the hospital is needed.

Prevention is the most effective weapon against anaphylaxis. If you have a severe allergic reaction, talk with your doctor. He or she may recommend that you get tested for triggers. Once you know what caused the reaction, you have a better chance of avoiding it in the future.

If you are at risk for anaphylaxis, you may be prescribed an auto-injector of epinephrine to use in case of emergencies. You may also want to wear medical identification jewelry or carry a wallet card to alert others.

By Emily Gurnon, Contributing Writer
Created on 06/08/1999
Updated on 03/25/2013
  • American Academy of Allergy, Asthma and Immunology. Allergies.
  • National Institute of Allergy and Infectious Diseases. Allergic diseases. Anaphylaxis.
  • National Institute of Environmental Health Sciences. Allergens & irritants.
  • Centers for Disease Control and Prevention. Allergies and hay fever.
Copyright © OptumHealth.
Top of page
General Drug Tools
General Drug Tools view all tools
Tools for
Healthy Living
Tools for Healthy Living view all tools
Search Tools
Search Tools view all tools
Insurance Plan Tools
Insurance Plan Tools view all tools