Skip to main content

Table 1 Clinical criteria for diagnosing anaphylaxis

From: CSACI position statement: transition recommendations on existing epinephrine autoinjectors

WAO 2020 Criteria [3]: anaphylaxis is likely when any one of the following 2 criteria are fulfilled: NIAID/FAAN Criteria [4]: fulfilling any 1 of the following 3 criteria indicates anaphylaxis is highly likely
Criterion 1: Criterion 1:
Acute onset of an illness (minutes to several hours) with simultaneous involvement of the skin, mucosal tissue, or both (ex: generalized hives, pruritus or flushing, swollen lips-tongue-uvula) and at least one of the following: Sudden onset of an illness (minutes to several hours), with involvement of the skin, mucosal tissue, or both (ex: generalized hives, itching or flushing, swollen lips-tongue-uvula) and at least one of the following:
  (i) Respiratory compromise (ex: dyspnea, wheeze-bronchospasm, stridor, reduced peak expiratory flow, hypoxemia)   (i) Sudden respiratory symptoms and signs (ex: shortness of breath, wheeze, cough, stridor, hypoxemia)
  (ii) Reduced BP or associated symptoms of end-organ dysfunction (ex: hypotonia, syncope, incontinence)   (ii) Sudden reduced BP or symptoms of end-organ dysfunction (ex: hypotonia, incontinence)
  (iii) Severe gastrointestinal symptoms (ex: severe crampy abdominal pain, repetitive vomiting), especially after exposure to non-food allergens Criterion 2:
Criterion 2: Two or more of the following that occur suddenly after exposure to a likely allergen or other trigger for that patient (minutes to hours)
Acute onset of hypotension or bronchospasm or laryngeal involvement after exposure to a known or highly probably allergen for that patient (minutes to several hours), even in the absence of typical skin involvement   (i) Sudden skin or mucosal symptoms and signs (ex: generalized hives, itch-flush, swollen lips-tongue-uvula)
    (ii) Sudden respiratory symptoms and signs (ex: shortness of breath, wheeze, cough, stridor, hypoxemia)
  (iii) Sudden reduced BP or symptoms of end-organ dysfunction (ex: hypotonia, incontinence)
Sudden gastrointestinal symptoms (ex: cramping abdominal pain, vomiting)
Criterion 3:
Reduced blood pressure (BP) after exposure to a known allergen for that patient (minutes to hours)
  (i) Infants and children: low systolic BP (age specific) or greater than 30% decrease in systolic BP
  (ii) Adults: systolic BP of less than 90 mm Hg or greater than 30% decrease from that person’s baseline