Table of Contents
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).

Airway
- Secure airway
- If stridor/airway obstruction, adrenaline nebuliser (5ml 1:1000) and consider intubation
Breathing
- 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
Circulation
- 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