What happens to the body during an anaphylactic reaction?

During an anaphylactic reaction an allergic response occurs to the trigger that a person is exposed to, and a protein called histamine is released from different tissues in the body. This quickly causes the symptoms of anaphylaxis including hives, swelling, dilated blood vessels with a drop in blood pressure, nausea, vomiting, and difficulty breathing. This is a life-threatening emergency that requires immediate medical attention. 
Paul M. Ehrlich, MD
Allergy & Immunology
During an anaphylactic reaction, a small amount of the offending protein in the food allergen is absorbed essentially intact into the body, bypassing the digestive process. The protein combines with at least two allergic immunoglobulin E (IgE) antibodies attached to a mast cell. The antibody has been made from a prior exposure to the protein -- this is an amnesic or remembered response. They fit with the allergic food protein like a key into a lock. This union of the food protein and two bound IgE antibodies activates the mast cell to release chemicals that are the cause of the allergic reaction and all the immune system forces come into play, like histamine, leukotrienes, and prostaglandins, and eosinophils, neutrophils, and platelets. With all these agents activated, epinephrine must be given early to call off the red alert and the catastrophe of anaphylaxis.
Asthma Allergies Children: A Parent's Guide

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Asthma Allergies Children: A Parent's Guide

Asthma and allergies are at epidemic proportions. It doesn't have to be that way. Two experienced pediatric allergists tell everything a conscientious parent needs to know about these conditions,...

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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.