subject: What is Anaphylaxis? [print this page] Anaphylaxis Anaphylaxis
What is Anaphylaxis? Anaphylaxis is a type of allergic reaction that affects the whole body. It is a response to a substance to which a person has become very sensitive. This allergic response is sudden, severe, and involves the whole body.
During an anaphylactic allergic reaction, tissues in different parts of the body release histamine and other substances. This causes constriction of the airways, resulting in wheezing; difficulty breathing; and gastrointestinal symptoms such as abdominal pain, cramps, vomiting, and diarrhea. Symptoms develop rapidly, often within seconds or minutes.
Shock may occur as a result of lowered blood pressure and blood volume. Hives and angioedema (hives on the lips, eyelids, throat, and/or tongue) often occur, and angioedema may be severe enough to cause obstruction of the airway. Prolonged anaphylaxis can cause heart arrhythmias.
Some drugs such as morphine, x-ray dye, and others may cause an anaphylactic like reaction on the first exposure. Anaphylaxis can occur in response to any allergen. Common causes include insect bites/ stings, food allergies, and drug allergies. Pollens and other inhaled allergens, which commonly cause allergic rhinitis, rarely cause anaphylaxis. Some people have an anaphylactic reaction with no identifiable cause.
Anaphylaxis occurs infrequently; it is life-threatening and can occur at any time. Risks include prior history of any type of allergic reaction.
Anaphylaxis is an emergency condition that requires immediate professional medical attention. Assessment of the ABCs (airway, breathing, and circulation) should be done in all suspected anaphylactic reactions. If indicated, CPR should be initiated. People with a history of severe allergic reactions may carry an Epi-Pen or other allergy kit, and should be assisted if necessary.
Reference:
Rice, Jane. (2005). Medical Terminology with Human Anatomy, fifth edition. Upper Saddle River, NJ: Prentice Hall, Inc.
