• Metaraminol is a sympathomimetic, adrenoceptor stimulant.
  • It directly and indirectly stimulates the alpha receptors in the sympathetic nervous system.
  • Alpha stimulation causes vasoconstriction with an increase in both systolic and diastolic blood pressure and an increase in systemic vascular resistance.
  • It has a positive inotropic effect on the heart and a peripheral vasoconstrictor action
  • Onset: 1 to 2 minutes; Duration: 20-60 minutes; Half-life: minutes
  • Adjunctive treatment of hypotension after adequate fluid resuscitation due to:
    • Haemorrhage
    • Cardiogenic shock
    • Septicaemia
    • Reactions to medications
    • Shock associated with brain damage due to trauma
  • Prevention and treatment of the acute hypotensive state occurring with anaesthesia
  • Hypersensitivity.
  • Hypovolaemia
  • MAOIs or within 14 days of such treatment
 Precautions / Notes
  • Use of Metaraminol with (MAOI’s) or tricyclic antidepressants may result in potentiation of the pressor effect.
  • Hypotension can be defined as less than 30% of the patient's base line SBP or for children (1-10 years): 70 mmHg +(2 x age).
  • Extravasation may cause tissue necrosis
  • Asthma – increased risk of allergy to sulfites (sodium metabisulfite is an excipient)
  • May increase risk of arrhythmias if given with other arrhythmogenic medications (e.g. digoxin)
  • Use with caution in the presence of heart or thyroid disease, hypertension or diabetes 
 Weight-based Calculations
IV Metaraminol for IV/IO
Presentation: /mL
Calculated dose:  in
IV Metaraminol for infusion
Presentation: /mL
Calculated dose:  to  ( to ) per hour.

Paramedics – Special Operations
  • ASMA Consult required
Critical Care


  • IV/IO:
    • IV/IO 0.5mg - 1mg, repeat >3 min
    • Dilute 10mg/1ml into 20ml NaCl 0.9% to provide a solution of 0.5mg/ml.
  • Infusion:
    • 20mg in 50ml in NaCl 0.9% at 0.5 to 5 ml/hr (0.4mg/ml) titrate to BP/haemodynamic status
Dose RangeRate of infusion (SD)


  • IV/IO:
    • 0.01mg/kg, repeat >3 min
    • Dilute 5mg/0.5ml into 50ml normal saline to provide solution of 0.1mg/ml
  • Infusion:
    • 0.15mg/kg in 50ml in normal saline at 1 to 10 ml/hr (0.05-0.5mcg/kg/min)
    • Titrate to BP / haemodynamic status.
Dose RangeRate of infusion (SD)
 Special Considerations

Administer dose cautiously as rapidly induced hypertensive response may cause:

  • Arrhythmias
  • Pulmonary oedema
  • Cerebral haemorrhage
  • Cardiac arrest.

Causes tissue necrosis, avoid extravasation.

10 mg/mL ampoule


Current mode:
Extended Care:
Colour assist:


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