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What is an anaphylactic reaction?


Anaphylaxis is a severe allergic reaction and medical emergency involving the entire body. It requires immediate medical help. Symptoms include difficulty breathing, loss of consciousness, and even death if not treated promptly and properly.

How does an anaphylactic reaction happen?

anaphylactic reaction is triggered the same way other, less severe allergic reactions are. The immune system overreacts to otherwise harmless substances. When this reaction is severe, as in anaphylaxis, it affects the entire body. The skin, respiratory system, heart and lungs, eyes, uterus, and bladder may be involved. This whole-body reaction may cause:

  • nausea
  • vomiting
  • abdominal cramps
  • hives
  • swelling of the lips
  • diarrhea
  • itchy skin
  • anxiety
  • headache
  • joint swelling
  • coughing, sneezing, wheezing
  • shortness of breath
  • itchy mouth and throat
  • nasal congestion
  • hoarseness
  • warmth and flushing
  • widespread, intense skin redness
  • uterine cramping
  • itchy, watery, swollen eyes
  • chest pain and tightness
  • difficulty breathing
  • low blood pressure
  • shock, loss of consciousness, and even death

If you have any of these symptoms after allergy testing or after exposure to an allergen, call 911 immediately.

If you think you've had an anaphylactic reaction, see an allergist for follow-up evaluation and treatment. The allergist can prescribe a medication called an epinephrine shot to carry with you and use if you begin to experience anaphylaxis in the future.


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