10 Common Allergy Triggers Slideshow Pictures Take the Quiz on Allergies Nasal Allergy Relief Slideshow Pictures

Medical Author:

Jerry R. Balentine, DO, FACEP

Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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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