Paeds · allergy-and-immunology
Anaphylaxis: recognition and emergency management
Also known as Anaphylactic shock · Severe allergic reaction · IgE-mediated systemic hypersensitivity · Adrenaline-requiring allergic emergency
Fellowship topic on anaphylaxis in children: the rapid, life-threatening, multisystem hypersensitivity reaction whose decisive treatment is early intramuscular adrenaline; the NIAID/FAAN definition and Brown severity grading; the IgE and non-IgE mast-cell and basophil mediator cascade producing upper-airway obstruction, bronchospasm and distributive shock; the triggers (food, drug, venom, idiopathic), the paediatric epidemiology of rising incidence and the fatal case profile (asthma, teenagers, delay in adrenaline); recognition that up to a fifth have no skin signs; the emergency algorithm — call help, remove trigger, IM adrenaline by weight/age band, positioning, oxygen and fluids, refractory management; tryptase timing; the biphasic reaction and observation periods; the discharge package of autoinjector, action plan and allergy referral; and ASCIA, EAACI, NICE and WAO regional guidance.
Checked against its sources on 11 Sept 2026
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Target exams
Red flags
- Stridor, drooling, tongue or lip swelling, or a sensation of throat closure — impending upper-airway obstruction; give IM adrenaline now and call for airway help
- Wheeze, marked respiratory distress, hypoxia or silent chest — severe bronchospasm; respiratory arrest from bronchospasm in pre-existing asthma is the most prevalent cause of death in food and drug anaphylaxis
- Hypotension, pallor, collapse, floppiness or altered consciousness — distributive shock; lie the child flat, legs raised, and give IM adrenaline and IV fluid boluses
- A child who needed two or more adrenaline doses, or who is on a beta-blocker — refractory or protracted anaphylaxis; escalate to an adrenaline infusion and senior or PICU support
- Failure or delay in giving IM adrenaline — the single most important reversible factor in fatal paediatric anaphylaxis; treat on suspicion, never wait for a rash or a test
Life stages
Care settings
Clinical exam formats
Board mappings
- General Paediatrics and Allergy: anaphylaxis — definition, recognition and emergency management
- Emergency and resuscitation: intramuscular adrenaline as first-line, weight/age dose bands, positioning and fluids
- Renewed curriculum — Allergy & immunology (LG): anaphylaxis pathophysiology, severity grading, refractory management
- Acute and critical care: biphasic reactions, observation periods and the adrenaline infusion
- General Paediatrics / ED: recognise anaphylaxis (including no skin signs) and give IM adrenaline without delay
- Resuscitation: ABCDE, oxygen, IV fluid bolus, escalating to an adrenaline infusion in refractory disease
- Long Case / Structured discussion: the child with a food allergy and a severe reaction — recognition, management, prevention and the action plan
- Communication station: explaining anaphylaxis, the adrenaline autoinjector and the school/childcare plan to a family
- Level 2 / 3 — Allergy: anaphylaxis as a time-critical allergic emergency; recognition, IM adrenaline and the observation and discharge package
- Patient safety and quality: avoidable factors in fatal anaphylaxis — delayed adrenaline, asthma, failure to provide an action plan
- Foundation of Practice (FOP): definition, triggers, clinical features and severity grading of anaphylaxis
- Applied Knowledge in Practice (AKP): emergency algorithm, adrenaline dosing, biphasic reaction and observation
- History-taking and management: the child who has had a severe allergic reaction
- Communication: teaching adrenaline autoinjector use and the action plan to a family and school
- General Pediatrics Content Outline — anaphylaxis: recognition and emergency management
- Allergy & Immunology: IgE and non-IgE mechanisms, triggers and the biphasic reaction
- Emergency Medicine: resuscitation, adrenaline dosing and the observation decision
- Patient Care: recognise and manage anaphylaxis with early IM adrenaline, fluids and the refractory pathway
- Systems-Based Practice: the action plan, autoinjector access and school/childcare anaphylaxis readiness
- Medical Knowledge: anaphylaxis pathophysiology, severity grading and observation periods
- Medical Expert: anaphylaxis diagnosis, adrenaline-first management and escalation
- Health Advocate: equitable autoinjector access, school policies and food-allergy community education
- Communicator: explaining anaphylaxis, the action plan and the autoinjector to families
The same emergency, two presentations
The textbook food reaction
The dangerous atypical case
Adrenaline is first-line, anterolateral thigh is the site, intramuscular is the route, further doses if no response after five minutes, and absence of a rash never excludes it. The rule that saves lives: treat on suspicion and give IM adrenaline early — the single reversible factor in fatal paediatric anaphylaxis is a delay in adrenaline. [3] [11]
Overview & Definition
Picture a four-year-old with a known peanut allergy who, ten minutes after biting into a biscuit at a birthday party, becomes flushed, starts to cough and wheeze, and tells his mother his throat feels funny. Within a minute his lips and tongue are swelling and he is drooling. His mother gives his adrenaline autoinjector into his thigh and calls an ambulance, and by the time help arrives he is already recovering. That sequence — a rapid multisystem reaction, an early intramuscular adrenaline, and a complete recovery — is anaphylaxis in its clearest form, and the whole fellowship answer hangs on understanding why adrenaline given early reverses everything while adrenaline given late may not. [1] [8]
Anaphylaxis is a severe, life-threatening generalised or systemic hypersensitivity reaction. It is acute in onset, usually progressing over minutes rather than hours, and it is multisystem — the skin and mucous membranes are involved in most but not all reactions, and the danger lies in the respiratory and cardiovascular compromise that follows. The 2006 NIAID/FAAN second symposium, summarised by Sampson and colleagues, gave the operational definition that clinicians now use at the bedside, because it allows treatment to begin without waiting for laboratory confirmation. [1] [5]
The clinical task has two halves that the examination separates sharply. The first half is the emergency: recognise the reaction, give intramuscular adrenaline early, support the airway, breathing and circulation, and escalate if it does not resolve. The second half is the aftermath: confirm the trigger, prevent the next reaction, and send the child home equipped — with an autoinjector, a written action plan, an allergy referral, and a family and school who know exactly what to do. A candidate who treats only the acute event and forgets the prevention package fails the question. [3] [8]
References13ShowHide
- [1]Sampson HA; Muñoz-Furlong A; Campbell RL; et al Second symposium on the definition and management of anaphylaxis: summary report--second National Institute of Allergy and Infectious Disease/Food Allergy and Anaphylaxis Network symposium. Ann Emerg Med, 2006.PMID 16546624
- [2]Brown SG Clinical features and severity grading of anaphylaxis. J Allergy Clin Immunol, 2004.PMID 15316518
- [3]Simons FE; Ardusso LR; Bilò MB; et al World allergy organization guidelines for the assessment and management of anaphylaxis. World Allergy Organ J, 2011.PMID 23268454
- [4]Muraro A; Worm M; Alviani C; et al EAACI guidelines: Anaphylaxis (2021 update). Allergy, 2022.PMID 34343358
- [5]Lieberman P; Nicklas RA; Oppenheimer J; et al The diagnosis and management of anaphylaxis practice parameter: 2010 update. J Allergy Clin Immunol, 2010.PMID 20692689
- [6]Baseggio Conrado A; Ierodiakonou D; Gowland MH; et al Food anaphylaxis in the United Kingdom: analysis of national data, 1998-2018. BMJ, 2021.PMID 33597169
- [7]Umasunthar T; Leonardi-Bee J; Hodes M; et al Incidence of fatal food anaphylaxis in people with food allergy: a systematic review and meta-analysis. Clin Exp Allergy, 2013.PMID 24118190
- [8]Sicherer SH; Simons FER; SECTION ON ALLERGY AND IMMUNOLOGY Epinephrine for First-aid Management of Anaphylaxis. Pediatrics, 2017.PMID 28193791
- [9]Lee S; Bellolio MF; Hess EP; et al Predictors of biphasic reactions in the emergency department for patients with anaphylaxis. J Allergy Clin Immunol Pract, 2014.PMID 24811018
- [10]Dribin TE; Sampson HA; Zhang Y; et al Timing of repeat epinephrine to inform paediatric anaphylaxis observation periods: a retrospective cohort study. Lancet Child Adolesc Health, 2025.PMID 40506197
- [11]Anagnostou A; Sharma V; Herbert L; et al Fatal Food Anaphylaxis: Distinguishing Fact From Fiction. J Allergy Clin Immunol Pract, 2022.PMID 34656799
- [12]Simons FE; Ardusso LR; Bilò MB; et al 2012 Update: World Allergy Organization Guidelines for the assessment and management of anaphylaxis. Curr Opin Allergy Clin Immunol, 2012.PMID 22744267
- [13]Cardona V; Ansotegui IJ; Ebisawa M; et al World allergy organization anaphylaxis guidance 2020. World Allergy Organ J, 2020.PMID 33204386