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A systemic type I (IgE mediated) life-threatening hypersensitivity reaction. 10-20% of cases may not have skin/mucosal changes (i.e. just bronchospasm or hypotension).

Immediately get help, call medical emergency team on 2222 (tell switchboard it is a medical emergency and the location) and remove allergen (i.e. stop any infusions).



  • Secure airway
  • If stridor/airway obstruction, adrenaline nebuliser (5ml 1:1000) and consider intubation


  • Apply sats probe
  • Attach 15L/minute oxygen via a non-rebreather mask
  • Bag-mask ventilation or intubation if apnoeic 
  • If wheeze, salbutamol (5mg) and ipratropium (500mcg) nebulisers with oxygen
  • ABG


  • Check blood pressure and apply 3-lead cardiac monitoring
  • Secure IV access (2 large-bore IV cannulas) – get IO access if unable to estabish IV access
  • IV fluids 500-1000ml 0.9% saline/Hartmann’s solution STAT fluid challenge initially (may need 3-5L IV fluids – give as fast as needed and titrate to BP)
  • Take bloods (including mast cell tryptase) and blood gas

Further short-term management

  • Document allergy on drug chart and event in notes
  • Admit for observation (at least 6 hours post-adrenaline because biphasic reactions can occur)
  • Consider oral non-sedating antihistamine
  • Monitor ECG
  • Further IV fluids if required

Longer-term management

  • Educate patient
  • Teach about self-injected adrenaline (Epipen)
  • Medic alert bracelet 
  • Refer to allergy clinic ± skin prick tests to identify allergens if unknown

Clinical incident form if given allergic antibiotic