Table of Contents
Definition of Anaphylaxis
Anaphylaxis is a severe hypersensitivity reaction (allergic reaction) in which the tissues of the throat swell, preventing air from getting to the lungs. Anaphylaxis, also called anaphylactic shock, is a type I hypersensitivity reaction that often develops rapidly, within minutes to an hour of exposure to the allergen. Hives, angioedema, and airway spasms are the most common symptoms. Some people also experience numbness or tingling of the lips and mouth.
Though anaphylaxis can be life-threatening, with prompt and appropriate treatment it is seldom fatal.
Symptoms and Treatment
The first line of treatment is epinephrine and antihistamine administered by injection, which immediately and effectively stop the progression of the hypersensitivity reaction. When airway (bronchial) symptoms are severe, the doctor may also administer an injectable corticosteroid medication. Swelling and related symptoms usually abate within a few minutes. Supportive treatment for symptoms often includes oxygen therapy and intravenous fluids.
Most people completely recover within a few hours.
Bee stings, peanuts, intravenous penicillin, and intravenous contrast dyes for radiology procedures are the most common allergens responsible for anaphylaxis. However, anaphylaxis is possible with any allergy.
Anaphylaxis is fatal for about 200 Americans each year.
Some people may benefit from desensitization, depending on the allergen responsible for the hypersensitivity reaction, to mitigate the immune response with future exposures. People who know they have severe allergies may get a doctor’s prescription for an anaphylaxis kit, which contains a prefilled syringe of injectable epinephrine.
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