Anaphylaxis Diagnostic Criteria (2020 WAO)

Decides whether a reaction meets the diagnostic criteria for anaphylaxis (2020 World Allergy Organization).

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Skin or mucosal involvement
Yes
Respiratory compromise
Yes

Result: Anaphylaxis criteria met by criterion 1 - anaphylaxis is highly likely. Epinephrine is first-line.

The tool opens with these values already filled in. Replace them with your own.

What the result means

Criterion 1
Acute skin or mucosal involvement PLUS at least one of respiratory compromise, reduced blood pressure or end-organ dysfunction, or severe gastrointestinal symptoms.
Criterion 2
Acute hypotension, bronchospasm or laryngeal involvement after a known or highly probable allergen - even with NO skin involvement.
Alternatives
Either alone is enough; they are not steps. The second exists precisely so a reaction with no rash still counts.
Caution
Anaphylaxis is a clinical diagnosis and epinephrine is first-line. Nothing here delays it, and not meeting either criterion does not exclude it.

What you enter

  • Skin or mucosal involvement
  • Respiratory compromise
  • Reduced BP or end-organ signs
  • Severe GI symptoms
  • Known or probable allergen
  • Hypotension
  • Bronchospasm
  • Laryngeal involvement
How this is calculated

Cardona V, Ansotegui IJ, Ebisawa M, et al. World Allergy Organization anaphylaxis guidance 2020. World Allergy Organ J. 2020;13(10):100472. Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.