What is anaphylaxis?

A severe allergic reaction can cause a condition called anaphylaxis, also known as anaphylactic shock. During anaphylaxis, air passages swell and restrict a person’s breathing.
Dr. Michael Roizen, MD
Internal Medicine
Not all allergies are just annoyances that make you itchy, runny or otherwise miserable for a period of time. Some can be serious or even fatal. While the worst a rash or red eye will do is crimp your enjoyment of the '80s flashback party, allergies that affect your lungs can be life threatening. This is called an anaphylactic reaction.

If you're allergic to a wasp sting, for instance, your blood vessels develop holes that leak fluid (you need blood inside the vessels not the fluid portion outside) and you may get so short of breath that no air can move (the fluid constricts the bronchi so much no air can pass, and you cannot even hear your wheezing). At this point, you need immediate help to open your airways, in the form of a potent allergy medication such as epinephrine. This is why many people who are at risk for anaphylactic reactions carry "epi pens."
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Anaphylaxis is a serious allergic reaction that is rapid in onset and may cause death. Common causes of anaphylaxis include food, medication, insect stings, and latex. Food allergy is believed to be the leading cause of anaphylaxis outside the hospital setting. The CDC reported that food allergies result in over 300,000 ambulatory-care visits a year among children.
Anaphylaxis is a severe, potentially life-threatening allergic reaction. It can occur within seconds or minutes of exposure to something you are allergic to, such as peanuts or the venom from a bee sting. Anaphylaxis requires an immediate trip to the emergency department and an injection of epinephrine. If anaphylaxis isn't treated right away, it can lead to unconsciousness or even death.
Paul M. Ehrlich, MD
Allergy & Immunology
The greatest danger from food allergy is anaphylaxis, also known as anaphylactic shock, a violent allergic reaction involving a number of parts of the body simultaneously. Like less serious reactions, anaphylaxis usually occurs after a person has already been exposed to an allergen, although it can appear to happen the first time a person eats a particular food.
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About one out of five Americans suffers from allergies. An allergy is an exaggerated response from the immune system to a substance such as dust, pollen, pet dander or mold. Other common triggers include foods such as peanuts and ...

milk; insect bites; and certain ingredients in cosmetics and jewelry. Allergies can cause anything from rashes and hives to itchy eyes, sneezing, coughing, diarrhea, vomiting, and wheezing.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.