Anaphylaxis

The answer first

Anaphylaxis is a clinical diagnosis treated with intramuscular adrenaline — everything else, including the tests, is refinement. Three rules carry you through the DWE, the resus bay and the viva ^{[2] [3]}:

1. Diagnose on pattern, not on tests or skin signs. The NIAID/FAAN criteria let you make the diagnosis on exposure-plus-multisystem-pattern alone; skin and mucosal signs are absent in up to one in five genuine reactions, and hypotension after a known trigger needs nothing else ^{[1] [3]}.
2. Adrenaline into the anterolateral thigh is the first and most important drug — antihistamines and corticosteroids never substitute for it. Delayed adrenaline, not absent steroids, is the recurring theme in fatality reviews; the Cochrane evidence for the second-line drugs is thin by comparison ^{[11] [6] [7]}.
3. The acute save is only half the job. Every patient gets a tryptase pair, an observation period calibrated to severity, and a discharge bundle — two adrenaline autoinjectors, device training, a written action plan, and specialist allergy referral ^{[9] [13]}.

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References23ShowHide

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