The course Objectives are

• Discuss the physiology related to allergies and anaphylaxis.
• Differentiate between a mild or localized allergic reaction and anaphylaxis.
• Explain the actions of medications used to treat anaphylaxis:
  • Epi nephrin
  • Benadryl, Zantac, Pepcid, Tagamet, and Albuterol.

An expert from the chapter Paramedic Recert EMS Care | 23-MCIT-F3-4124 | Immunological Emergencies

A person must first be exposed to a specific antigen to develop hypersensitivity. During the first exposure, the antigen enters the body through injection, ingestion, inhalation, or absorption. The antigen then activates the immune system. In susceptible individuals, large amounts of I-g-E antibodies are produced. I-g-E antibodies leave the lymphatic system and bind to I-g-E-specific Fc receptors on the cell membranes of basophils that are circulating in the blood, and to mast cells that are in tissues surrounding the blood vessels. The antibodies remain there and are inactive until the same antigen is introduced into the body a second time. With the next exposure to the specific antigen, the allergen cross-links at least two of the cell-bound I-g-E molecules. This results in degranulation (release of internal substances) of mast cells and basophils and the onset of anaphylaxis.