Table 4 Clinical criteria for diagnosing anaphylaxis [21,22,23]

1. Acute onset of an illness (minutes to several hours) with involvement of the skin, mucosal tissue, or both (e.g., generalized hives, pruritus or flushing, swollen lips-tongue-uvula) and at least 1 of the following:

    a. Respiratory compromise (e.g. dyspnea, wheeze, bronchospasm, stridor, reduced PEF, hypoxemia)

    b. Reduced BP or associated symptoms of end-organ dysfunction (e.g. hypotonia [collapse], syncope, incontinence)

2. Two or more of the following that occur rapidly after exposure to a likely allergen for that patient (minutes to several hours):

    a. Involvement of the skin-mucosal tissue (e.g., generalized hives, itch-flush, swollen lips-tongue-uvula)

    b. Respiratory compromise (e.g., dyspnea, wheeze, bronchospasm, stridor, reduced PEF, hypoxemia)

    c. Reduced BP or associated symptoms (e.g., hypotonia [collapse], syncope, incontinence)

 d. Persistent GI symptoms (e.g., painful abdominal cramps, vomiting)

3. Reduced BP after exposure to a known allergen for that patient (minutes to several hours):

    a. Infants and children: low systolic BP (age specific) or > 30% decrease in systolic BP^a

    b. Adults: systolic BP < 90 mmHg or > 30% decrease from that person’s baseline