Anaphylactic shock, or anaphylaxis, occurs when the body reacts to an allergen and triggers a series of symptoms that can be dangerous and life-threatening. Anaphylaxis typically involves a swollen throat and difficult breathing, but it also produces low blood pressure, weakness, chest tightness and fainting. Vomiting and diarrhea can also occur, and anaphylaxis can produce an itchy skin rash as well.
Symptoms of anaphylaxis typically develop within minutes of exposure to the allergen. In rarer instances, anaphylaxis occurs several hours later. About 25 percent of those with anaphylaxis experience a second wave of anaphylactic shock, called biphasic anaphylaxis, a few hours after the first wave.
Anaphylaxis usually occurs in reaction to a food allergy, but other allergens also can trigger anaphylactic shock. For example, allergies to medications, latex or insect stings can be triggers of anaphylaxis. In rarer instances, exercise causes anaphylaxis.
Treatment of Anaphylactic Shock
Anaphylaxis is life-threatening and should be viewed as a medical emergency. If you suspect you might have it, it’s important to work closely with a doctor to form an action plan for dealing with the condition.
Step one, of course, is to take great care to avoid the potential allergen, whether that's shellfish, peanuts or bee stings. People prone to anaphylaxis should also have a supply of epinephrine on hand at all times. When administered, this injectable rescue medication can stop anaphylactic shock. It's known as an epinephrine auto-injector, or an EpiPen.
Even if epinephrine is administered, it’s important to obtain emergency medical treatment for the person who experienced anaphylactic shock. Further evaluation and treatment is needed to ensure that the anaphylaxis has passed and that the person is safe.
SOURCES: American Academy of Allergy, Asthma & Immunology; Food Allergy Research and Education