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Allergies Health Center

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Understanding Allergies -- the Basics

What Triggers Anaphylactic Shock?

The most severe and dangerous allergic reaction is anaphylaxis, or anaphylactic shock, which typically begins within minutes after exposure and advances quickly. Although any allergen can trigger anaphylactic shock, the most common are insect stings, certain foods (such as shellfish and nuts), and injections of certain drugs. Treatment of anaphylaxis typically involves an injection of epinephrine to slow the progression and symptoms, and in severe cases, cardiopulmonary resuscitation (CPR) may be needed.

If you have severe allergies, you should keep two auto-injectors of epinephrine with you at all times. If you experience any sign of anaphylaxis, do not hesitate to use the epinephrine auto-injector, even if those symptoms do not appear to be allergy related. Using the auto-injectoras a precaution will not harm you.

Even after using the auto-injector, you should call 911 immediately.

WebMD Medical Reference

Reviewed by Jennifer Robinson, MD on October 21, 2015
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