Cardinal features of anaphylaxis

The cardinal features of anaphylaxis are:

  • Itchy, urticarial rash.
  • Progressive, painless swelling (angioedema) about the face and mouth, which may be preceded by itchiness, tearing, nasal congestion or facial flushing.
  • Gastrointestinal symptoms, including cramps/abdominal pain and vomiting.
  • Sudden reduced blood pressure or symptoms of end-organ dysfunction (e.g., hypotonia and incontinence).
  • In infants, symptoms may also include fussiness, irritability, drowsiness or lethargy.