Anaphylaxis

Anaphylaxis (pronounced “an-ah-fi-LAK-sis”) is a severe allergic reaction. It can be life-threatening if you don’t get treatment right away. Food allergies are one of the main causes of anaphylaxis. Other causes include stinging insects, medications and latex.

The only treatment for anaphylaxis is epinephrine, which comes as a shot you inject into your thigh. Even with treatment, a person experiencing anaphylaxis needs to go to the nearest emergency room. With prompt treatment, most people make a full recovery.

What happens during anaphylaxis?

When you’re allergic to something, your immune system overreacts by releasing chemicals like histamine. Symptoms of anaphylaxis include swelling, wheezing, shortness of breath and difficulty swallowing. An anaphylactic reaction may affect several areas of your body at once.

Call 911 (or your emergency services number) and go to the nearest emergency room if you, or someone around you, are experiencing anaphylaxis, even if you’ve already administered epinephrine.

What are the stages of anaphylaxis?

Anaphylaxis tends to happen suddenly and quickly. There often isn’t a warning period, but there can be mild signs like hives or flushed skin. Some healthcare providers break the stages of anaphylaxis into four categories:

• Stage one: Mild anaphylaxis is the first stage and can cause symptoms like skin rash or redness, itching or hives.
• Stage two: Moderate anaphylaxis happens when a person has more widespread and extensive symptoms like skin rash and hives that are spreading or mild swelling in their lips or tongue.
• Stage three: Severe anaphylaxis happens next and involves a person displaying signs of difficulty breathing, extensive swelling, weak pulse or dizziness. A person in stage three anaphylaxis is experiencing a condition called anaphylactic shock.
• Stage four: Life-threatening anaphylaxis is the last stage and involves a person losing consciousness, being unable to breathe and having inadequate blood flow to vital organs. A person in this stage needs immediate medical attention to avoid death.

What is anaphylactic shock?

A person who has an anaphylactic reaction can go into anaphylactic shock when their blood pressure drops dangerously low. Bronchial tissues, which help carry air, may begin to swell and cause wheezing, shortness of breath and even loss of consciousness. Anaphylactic shock requires immediate treatment to save the person’s life.

How common is anaphylaxis?

Estimates vary, but the most recent data suggests that people in the U.S. have a 0.05% and 2% lifetime chance of experiencing anaphylaxis.