What are symptoms of anaphylaxis (anaphylactic shock)?

Anaphylactic shock causes the sudden onset of severe symptoms that may involve different parts of the body. These symptoms can include hives, difficulty breathing or swallowing, chest tightness, diarrhea, light-headedness, palpitations, throat swelling, wheezing, nausea or vomiting, swelling of the eyes or face, and nasal congestion, anxiety, and pale color. 

Dr. Paul M. Ehrlich, MD
Allergist & Immunologist

Anaphylaxis can produce severe symptoms in as little as five to fifteen minutes, although life-threatening reactions may progress over hours. Signs of such a reaction include: difficulty breathing, feeling of impending doom, swelling of the mouth and throat, a drop in blood pressure, and loss of consciousness. The sooner anaphylaxis is treated, the greater the chance of surviving. The episode should involve a trip to the emergency room, even if symptoms seem to subside on their own.

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Signals of anaphylaxis include:

  • A rash 
  • Tightness in the chest and throat 
  • Swelling of the face, neck and tongue 
  • Dizziness or confusion

Anaphylaxis is a life-threatening emergency.

Continue Learning about Allergies



About one out of five Americans suffers from allergies. An allergy is an exaggerated response from the immune system to a substance such as dust, pollen, pet dander or mold. Other common triggers include foods such as peanuts and ...

milk; insect bites; and certain ingredients in cosmetics and jewelry. Allergies can cause anything from rashes and hives to itchy eyes, sneezing, coughing, diarrhea, vomiting, and wheezing.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.