Quick Chart
  • Any acute onset of hypotension or bronchospasm or upper airway obstruction where anaphylaxis is considered possible, even if typical skin features are not present OR
  • Any acute onset illness with typical skin features (urticarial rash or erythema/flushing, and/or angioedema), PLUS involvement of respiratory and/or cardiovascular and/or persistent severe gastrointestinal symptoms”, (ASCIA, 2010).

If allergic reaction is deemed to involve more than two body systems, and it is therefore no longer localised, anaphylaxis should be considered.

Read the complete article; Anaphylaxis in the Medical Library > Pathophysiology.

Clinical Presentation
Mild to moderate allergic reactions:
  • Swelling of lip, face, eyes
  • Tingling mouth
  • Abdominal pain, nausea and/or vomiting (these are signs of severe allergic reaction to insects and medications)
  • Urticaria, itching and welts (weal-like swellings)


  • Chest tightness
  • Decreased mental status
  • Subjective airway impairment or swelling (swollen tongue, laryngeal oedema, stridor)
  • Swelling/tightness in throat
  • Difficult/noisy breathing
  • Difficulty talking and/or hoarse voice
  • Wheeze or persistent cough
  • Hypotension
  • Pale and floppy (young children)
Exclusion Criteria
Exclusion Criteria
Risk Assessment
  • If antihistamines administered prior to arrival, determine if drowsy/non-drowsy.
    • If non-drowsy antihistamines administered and patient has decreased alertness, suspect anaphylaxis.
  • Upright positioning (e.g. standing/sitting upright) coupled with significant hypotension can precipitate death.
  • Hypotension in adults can be defined as a systolic BP of less than 90 mmHg or greater than 30% decrease from that person’s baseline and in children less than (70 mmHg + [2 x age]) from 1 to 10 years.
  • Consider early the need for advanced airway management.
  • Position appropriately with dependent drainage for secretions – this is usually on the side. Patient should not be in sitting position unless absolutely necessary (consider semi-recumbent position) and legs should be outstretched (i.e. not in a chair). Avoid standing or walking even if they appear to have recovered.
  • Patients should not walk post EpiPen / IM Adrenaline administration due to risk of collapse.
  • Be cautious of atypical presentations, if hypotensive and non-traumatic / cardiogenic cause, consider anaphylaxis.
Primary Care
Intermediate Care (EMT / Level 2)
  • Consider applying cardiac monitor if trained and authorised
  • Consider administering further doses of adrenaline if no significant improvement
  • Consider Salbutamol if required for persistent wheeze
  • Monitor patient persistently, recording full observations every 10 minutes (or 5 minutes if time critical)
  • Transport Priority 1 if patient time critical, pre-notifying receiving facility
Advanced Care (AP)
  • Consider Adrenaline if required
  • Consider administering further doses of Adrenaline if no significant improvement
  • Apply cardiac monitoring
  • Obtain vascular access
  • Consider fluid therapy if required for treatment of anaphylactic shock
  • Consider Salbutamol if required for persistent wheeze
  • Re-assess and manage accordingly
  • Monitor patient persistently, recording full observations every 10 minutes (or 5 minutes if time critical)
  • Transport Priority 1 if patient time critical, pre-notifying receiving facility
Critical & Extended Care (CCP, PSO)
  • Consider advanced airway if indicated
  • Consider ASMA authorisation for adrenaline infusion
Additional Information
  • Catastrophic hypotension could render IM Adrenaline ineffective
  • Clinical deterioration
  • Airway compromise
  • Dysrhythmia
  • Cardiac arrest
  • Patient should be taken to a medical facility where they can be monitored for 4 hours after the last dose of adrenaline


Document Control

Clinical Services

Responsible Manager
Head of Clinical Services

Published Date

Review Date

St John Ambulance Western Australia Ltd © Copyright 2020, All Rights Reserved

Privacy Policy | Copyright Statement & Disclaimer