EMT- Chapter 21: Allergic and Anaphylactic Reactions

Allergen

a substance (antigen) that enters the body by ingestion, injection, inhalation, or absorption and triggers an allergic reaction

Allergic reaction

a misdirected and excessive response by the immune system to a foreign substance or an allergen

Anaphylactic reaction

a reactive release of chemical mediators that produce bronchoconstriction, vasodilation, capillary permeability, and increased mucus production leading to airway and respiratory compromise and hypoperfusion. Also called anaphylaxis

Anaphylactic shock

a shock (hypoperfusion) state that results from dilated and leaking blood vessels related to sever allergic reaction. Also called anaphylaxis or anaphylactic reaction

Anaphylactoid reaction

a reaction to a foreign substance that resembles an anaphylactic reaction that may occur on first exposure to the substance, without the prior immune system sensitization that characterizes an anaphylactic reaction

Anaphylaxis

another term for anaphylactic reaction

Antibodies

special proteins produced by the immune system that search out antigens and combine with and help to destroy them

Antigen

a foreign substance that enters the body and triggers an immune response

Endotracheal intubation

placement of a tube through the mouth into the pharynx, larynx, and trachea to establish an airway

Histamine

the primary chemical mediator released from the mast cells in an anaphylactic reaction

Hives

raised, red blotches associated with allergic and anaphylactic reactions

Hypersensitivity

A state of altered reactivity to an antigen, or foreign substance, that causes allergic reactions to that substance.

IgE-medicated anaphylactic reaction

a term for anaphylaxis derived from the immunoglobulin E antibody that the body produces in response to an anaphylaxis-causing allergen

Immune response

production of antibodies by the immune system to fight off invasion by foreign substances

Immune system

the body's defense mechanisms against invasion by foreign substances

Malaise

general feeling of weakness or discomfort

non-IgE-mediated reaction

a reaction to a foreign substance that resembles an anaphylactic reaction that may occur on first exposure to the substance, without the prior immune system sensitization that characterizes an anaphylactic reaction

Sensitization

exposure to an allergen that results in hypersensitivity to that allergen