Symptoms of Anaphylaxis

Learn about the symptoms of anaphylaxis, a severe and potentially life-threatening allergic reaction.

Anaphylaxis often begins within minutes after a person eats a problem food. Less commonly, symptoms may begin hours later. Up to 20 percent of patients have a second wave of symptoms hours or even days after their initial symptoms have subsided. This is called biphasic anaphylaxis.

Anaphylaxis is highly likely to be occurring when any ONE of the following happens within minutes to hours after ingestion of the food allergen:

 

1. A person has symptoms that involve the skin, nose, mouth or gastrointestinal tract and either:

  • Difficulty breathing, or
  • Reduced blood pressure (e.g., pale, weak pulse, confusion, loss of consciousness)

 

2. A person was exposed to a suspected allergen, and two or more of the following occur:

  • Skin symptoms or swollen lips
  • Difficulty breathing
  • Reduced blood pressure
  • Gastrointestinal symptoms (e.g., vomiting, diarrhea, cramping)

 

3. A person was exposed to a known allergen, and experiences:

  • Reduced blood pressure, leading to weakness or fainting

 

Learn more about how to respond and react to anaphylaxis with this free training