Emergency treatment of anaphylaxis: guidelines for healthcare providers

Resuscitation Council UK · May 2021 edition

Clinical guideline for recognition and emergency management of anaphylaxis in all healthcare settings, emphasising intramuscular adrenaline.

In one sentenceGive IM adrenaline (500 micrograms adult, 300 micrograms 6–12y, 150 micrograms 6mo–6y, 100–150 micrograms <6mo) into anterolateral thigh immediately for anaphylaxis; repeat after 5 minutes if ABC problems persist; refractory anaphylaxis (no improvement after 2 doses) requires IV adrenaline infusion and critical care.

Issuer: Resuscitation Council UK
Edition: May 2021 edition
Audience: All healthcare providers expected to treat anaphylaxis (doctors, nurses, paramedics) in hospital and out-of-hospital settings; specific guidance for anaesthetists, emergency medicine, paediatrics, allergy specialists.
Evidence: GRADE-ADOLOPMENT framework (Evidence to Decision); systematic review and peer-reviewed evidence tables published in Resuscitation journal; expert consensus where RCT evidence unavailable
Reviewed: 23 Oct 2026 · GMJ

Read the original on Resus Council UK Download PDF

Summary by GMJ Guidelines Desk•Reviewed by Prof. Giorgi Pkhakadze, MD, MPH, PhD•Record updated 23 Oct 2026•Next check Apr 2027

What this guideline says

GMJ summary

This Resuscitation Council UK guideline provides a comprehensive, evidence-based approach to the emergency treatment of anaphylaxis for all healthcare providers. Anaphylaxis is defined as a serious systemic hypersensitivity reaction with sudden onset, rapid progression, and potentially life-threatening compromise of airway, breathing, and/or circulation. The guideline emphasises that intramuscular adrenaline is the first-line treatment, given early in the anterolateral thigh, and repeated after 5 minutes if symptoms persist.

The guideline introduces two treatment algorithms: one for initial treatment and a second for refractory anaphylaxis, defined as reactions requiring ongoing treatment despite two appropriate doses of IM adrenaline. Key changes from the 2008 edition include greater emphasis on early repeat IM adrenaline, a risk-stratified approach to observation duration (minimum 6 hours, up to 12 hours for severe reactions), and removal of routine corticosteroids from emergency treatment. The guideline stresses that all patients should be referred to specialist allergy services and that healthcare settings must have adrenaline 1 mg/mL ampoules immediately available.

The document provides detailed guidance on recognition (sudden onset with ABC problems plus usually skin/mucosal changes), patient positioning (lying flat for hypotension, semi-recumbent if breathing easier), IV fluid resuscitation (500–1000 mL bolus for adults, 10 mL/kg for children), and the limited role of antihistamines and corticosteroids. Refractory anaphylaxis requires critical care support with IV adrenaline infusion (0.5–1.0 mL/kg/h of 1 mg in 100 mL preparation), large-volume fluid resuscitation, and consideration of alternative vasopressors. The guideline applies to all age groups and healthcare settings, with specific sections on peri-operative anaphylaxis, pregnancy, and cardiorespiratory arrest.

Key points

For clinicians — doses and thresholds as stated in the guideline

Give intramuscular adrenaline 500 micrograms (0.5 mL of 1 mg/mL) for adults/children >12 years; 300 micrograms (0.3 mL) for 6–12 years; 150 micrograms (0.15 mL) for 6 months–6 years; 100–150 micrograms (0.1–0.15 mL) for <6 months, into anterolateral thigh using a needle long enough to reach muscle (21G or 23G).
Repeat IM adrenaline after 5 minutes if airway, breathing, or circulation problems persist; most community reactions resolve with 1–2 doses but around 10% need a second dose.
Refractory anaphylaxis (no improvement after two IM adrenaline doses) requires urgent critical care support and IV adrenaline infusion: mix 1 mg in 100 mL 0.9% sodium chloride, start at 0.5–1.0 mL/kg/h, titrate to response.
Give rapid IV fluid bolus (500–1000 mL adult, 10 mL/kg child) for hypotension or poor response to first adrenaline dose; up to 3–5 litres may be needed in severe shock due to fluid extravasation of up to 35% circulating volume within 10 minutes.
Keep patients with cardiovascular instability lying flat (legs raised if possible) to maximise venous return; sudden postural change can cause collapse and death. Semi-recumbent position acceptable if only respiratory symptoms and no hypotension. Pregnant patients lie on left side.
Antihistamines (oral cetirizine preferred, 10–20 mg adult) are third-line for skin symptoms only after stabilisation; do not give instead of adrenaline. Corticosteroids are no longer advised for routine emergency treatment.
Observe minimum 6 hours after resolution if good response to single adrenaline dose given within 30 minutes; 12 hours if required >2 doses, severe asthma, severe respiratory compromise, previous biphasic reaction, or possibility of continuing allergen absorption. Biphasic reactions occur in ~5%, median time 12 hours.
Measure serum mast cell tryptase ideally at three time-points: as soon as feasible, at 1–2 hours (peak), and ≥24 hours after resolution (baseline). Elevated tryptase (>11.4–14 micrograms/L or >[baseline×1.2]+2) supports diagnosis but normal level does not exclude anaphylaxis, especially food-induced.

IM adrenaline doses by age

Table extracted from the guideline

Age/weight	Dose	Volume of 1 mg/mL adrenaline
< 6 months	100–150 micrograms	0.1–0.15 mL
6 months – 6 years	150 micrograms	0.15 mL
6–12 years (or small/prepubertal)	300 micrograms	0.3 mL
≥12 years and adults	500 micrograms	0.5 mL

Source: Resuscitation Council UK, Emergency treatment of anaphylaxis: guidelines for healthcare providers. Reproduced in summary form.

What changed in this edition

Versus the previous edition

Greater emphasis on repeating IM adrenaline after 5 minutes if airway/breathing/circulation problems persist, rather than waiting longer.
Specific adrenaline dose now included for infants below 6 months of age (100–150 micrograms IM).
Two separate algorithms introduced: initial treatment of anaphylaxis and treatment of refractory anaphylaxis (defined as no improvement after two appropriate IM adrenaline doses).
IV fluids emphasised for refractory anaphylaxis and must be given early if hypotension/shock present (10 mL/kg child, 500–1000 mL adult bolus).
Antihistamines downgraded to third-line intervention, should not be used to treat ABC problems; non-sedating oral antihistamines (e.g. cetirizine) preferred over chlorphenamine after stabilisation.
Corticosteroids (e.g. hydrocortisone) no longer advised for routine emergency treatment of anaphylaxis; may be considered for refractory reactions after initial resuscitation.
Risk-stratified observation duration guidance: fast-track discharge (2 hours) possible if good response to single adrenaline dose within 30 minutes; minimum 6 hours for most; 12 hours if severe reaction, >2 adrenaline doses, severe asthma/respiratory compromise, previous biphasic reaction, or continuing allergen absorption.
Increased emphasis on maintaining supine position and avoiding sudden postural changes, which can cause cardiovascular collapse and death.

From the guideline

Verbatim

“Adrenaline is the first-line treatment for anaphylaxis. Give intramuscular (IM) adrenaline early (in the anterolateral thigh) for Airway/Breathing/Circulation problems.”

— Resuscitation Council UK, Emergency treatment of anaphylaxis: guidelines for healthcare providers, Key recommendations for clinical practice, page 7 (2021)

Editor’s perspective

Why this matters for Georgia and the region

Prof. Giorgi Pkhakadze, MD, MPH, PhD

Editor-in-Chief, Georgian Medical Journal · Chair, Public Health Institute of Georgia · WHO consultant, health and migration

As Editor-in-Chief of the Georgian Medical Journal and Chair of the Public Health Institute of Georgia, I recognise this guideline addresses a critical gap in emergency care capacity across our region. The most important recommendation for Georgian clinicians is the emphasis on early repeat IM adrenaline at 5 minutes if symptoms persist—our experience suggests healthcare providers often hesitate to give a second dose, waiting too long and allowing progression to refractory shock that requires intensive care resources we may not have readily available in all settings. The risk-stratified observation protocol is practical for Georgian hospitals and should be incorporated into national emergency medicine protocols. The realistic implementation challenge is ensuring that all healthcare settings, including rural primary care facilities and polyclinics where immunisations are delivered, have immediate access to 1 mg/mL adrenaline ampoules, that staff are trained annually in recognition and IM injection technique, and that we establish clear referral pathways to the limited specialist allergy services currently available in Tbilisi—telemedicine consultations may partially address this gap for cases outside the capital.

ORCID 0000-0001-7609-4515 · Perspective written for the GMJ Guidelines Library, 23 Oct 2026

Applicability

Georgia and the South Caucasus

This guideline is directly applicable to Georgia and the South Caucasus, where anaphylaxis incidence is rising in parallel with global trends in allergic disease. Georgian healthcare providers in emergency departments, primary care, paediatric services, and peri-operative settings should adopt the IM adrenaline-first approach and ensure 1 mg/mL adrenaline ampoules are available in all clinical areas, including immunisation settings as per national programmes. The risk-stratified observation protocol is feasible in Georgian hospitals with emergency departments and can inform national protocols. Key implementation considerations include: training healthcare workers (especially in primary care and rural areas) to recognise anaphylaxis and give IM adrenaline confidently; establishing referral pathways to specialist allergy services (currently limited in Georgia); ensuring auto-injector availability and patient/family training; and adapting the guideline for settings with limited critical care capacity, where early recognition and IM adrenaline become even more critical to prevent progression to refractory shock requiring IV adrenaline infusions.

Questions this guideline answers

Quick answers

When exactly should I give the first dose of IM adrenaline?

Give IM adrenaline as soon as you recognise anaphylaxis: sudden onset with airway and/or breathing and/or circulation problems, usually with skin/mucosal changes (flushing, urticaria, angioedema). If in doubt, give IM adrenaline – a single dose is well-tolerated and poses minimal risk. Do not wait for skin changes (absent in up to 20% of cases) or delay for investigations.

How do I know if a patient needs a second dose of adrenaline?

Reassess airway, breathing, and circulation after 5 minutes. If problems persist (continued wheeze, stridor, respiratory distress, hypotension, tachycardia, reduced consciousness), give a second IM adrenaline dose immediately. Monitor vital signs (respiratory rate, SpO₂, heart rate, blood pressure, consciousness) continuously. Around 10% of reactions need more than one dose.

What defines refractory anaphylaxis and what do I do?

Refractory anaphylaxis is anaphylaxis with no improvement in respiratory or cardiovascular symptoms despite two appropriate doses of IM adrenaline. Call for critical care support urgently (resuscitation team in hospital, ambulance service out-of-hospital). Give IV fluid bolus (500–1000 mL adult, 10 mL/kg child). An IV adrenaline infusion must be started by experienced specialists: mix 1 mg adrenaline in 100 mL 0.9% sodium chloride, start at 0.5–1.0 mL/kg/h depending on severity, titrate to response. Continue IM adrenaline every 5 minutes until IV infusion is running.

How long should I observe a patient after anaphylaxis before discharge?

Risk-stratified approach: Fast-track discharge after 2 hours observation (from resolution) is acceptable if good response to single adrenaline dose given within 30 minutes of onset, complete resolution, patient has adrenaline auto-injectors and training, and adequate supervision at home. Minimum 6 hours observation for most patients. Observe at least 12 hours if: severe reaction needing >2 adrenaline doses, severe asthma or severe respiratory compromise, previous biphasic reaction, possibility of continuing allergen absorption, late-night presentation, or difficult access to emergency care. Warn all patients about biphasic reactions (recurrence of symptoms hours later, occurs in ~5%, median 12 hours) and advise to return if symptoms recur.

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