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Severe Allergic Reaction (Anaphylactic Shock) (cont.)

Severe Allergic Reaction Symptoms

The symptoms of anaphylaxis can vary. In some people, the reaction begins very slowly, but in most the symptoms appear rapidly and abruptly.

  • The most severe and life-threatening symptoms are difficulty breathing and loss of consciousness.
    • Difficulty breathing is due to swelling and/or spasm in the airways (which can include swelling of the tongue or the airways). In very rare cases, breathing can stop altogether.
    • Loss of consciousness is due to dangerously low blood pressure, which is called "shock."
    • In the most serious cases, the heart can stop pumping altogether.
    • These events can lead to death from anaphylaxis.
  • While some symptoms are life threatening, others are merely uncomfortable. Generally, a reaction must involve at least two different body systems, such as skin and heart, to be considered anaphylaxis.
    • Skin: Most anaphylactic reactions involve the skin.
      • Hives, welts, or wheals (raised bumps): Hives can cause severe itching
      • Generalized erythema (redness)
      • Swelling in the face, eyelids, lips, tongue, throat, hands, and feet
    • Breathing: Swelling of the surrounding tissues narrows the airways.
      • Difficulty breathing, wheezing, chest tightness
      • Coughing, hoarseness
      • Nasal congestion, sneezing
    • Cardiovascular: Blood pressure may drop to dangerously low levels.
      • Rapid or irregular heart beat
      • Dizziness, faintness
      • Loss of consciousness, collapse
    • General
      • Tingling or sensation of warmth - Often the first symptom
      • Difficulty swallowing
      • Nausea, vomiting
      • Diarrhea, abdominal cramping, bloating
      • Anxiety, fear, feeling that you are going to die
      • Confusion
Medically Reviewed by a Doctor on 6/10/2014
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