• A naturally occurring sympathomimetic agent
  • Causes peripheral vasoconstriction
  • Stimulation of cardiac conduction system causes increased contractions
  • Causes bronchial smooth muscle relaxation the helps alleviate bronchospasm, wheezing and dyspnoea
  • Alleviates pruritus, urticaria, and angioedema and relieves gastrointestinal and genitourinary symptoms due to relaxant effects on the smooth muscle of the stomach, intestine, uterus, and urinary bladder


  • Onset of action is 60 seconds; duration of effect is short and half-life is 5 minutes.
  • There are no absolute contraindications to adrenaline
 Precautions / Notes
  • ALWAYS give adrenaline auto-injector FIRST and then asthma reliever puffer if someone with known asthma and allergy to food, insects or medication has sudden breathing difficulty (e.g. wheeze, persistent cough or hoarse voice), even if there are no skin symptoms
  • Patient’s own injector may be used
  • Do not walk or stand patient pre or post adrenaline administration - usually a minimum of 1 hour after 1 dose of adrenaline and 4 hours if more than 1 dose of adrenaline given
  • Advise transport to a medical facility due to risk of bi-phasic reactions
 Weight-based Calculations
Cefazolin for fractures/prophylaxis
Presentation: /mL
Calculated dose:  in

  • Position patient supine, or in a left lateral / recovery position if patient unconscious or pregnant
  • Prepare adrenaline auto-injector as per device available (Anapen® or EpiPen®)

Children 7.5-20kg (aged around one to five years):

  • EpiPen® Jr (150 MICROg) or
  • Anapen® 150 (Jr) (150 MICROg)

Children over 20kg and adults

  • EpiPen® (300 MICROg) or
  • Anapen® 300 (300 MICROg)

Children and adults over 50kg 

  • Anapen® 500 (500 MICROg) or
  • Anapen® 300 (300 MICROg) or
  • EpiPen® (300 MICROg)

EpiPen/Anapen can both be repeated at 5-minute intervals as clinically required

 Special Considerations
  • Tachycardia, palpitations
  • Arrhythmias
  • Hypertension (may be marked)
  • Tremor
  • Anxiety
  • EpiPen® (yellow label): 300 MICROg
  • EpiPen Jnr® (green label): 150 MICROg
  • Anapen® Jr: 150 MICROg
  • Anapen® 300: 300 MICROg
  • Anapen® 500: 500 MICROg



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