A short acting synthetic narcotic analgesic

  • Fentanyl: 450 microg/1.5 mL (300 microg/mL); intra-nasal administration only
  • Fentanyl Citrate: 100 microg/2 mL ampoule (50 microg/mL); IV/IO only
  • Fentanyl Citrate: 500 microg/10 mL ampoule (50 microg/mL); IV/IO only

    Pharmacology Review 

    • Moderate to severe pain.
    • Acute Coronary Syndromes where GTN has been ineffective
    • Hypersensitivity to fentanyl
    • Child <1 year of age (for IV / IO only)
    • Occluded nasal passages or epistaxis (for IN only)
     Precautions / Notes
    • Elderly patients
    • Respiratory depression: especially those at risk e.g. patients with severe COPD
    • Patients currently on MAO inhibitors or MAO inhibitor use within previous 14 days
    • Caution in larger doses of women in active labour
    • Use of IV Ketamine as analgesic prior to minimum (age dependant) dose of IV Fentanyl requires ASMA authorisation:
      • Paediatric: 100 microg
      • Adult < 70 years old: 200 microg
      • Adult > 70 (or frail): 100 microg
    • Administer slowly
    • Cease administration prior to calculated dose if desired effect is obtained.
    • Patients under extended care (e.g. 'ramped' patients) who have already been administered pain relief should have careful consideration with regards to the dosages of fentanyl administered, titrating only to effect.

    Fentanyl Citrate for IV / IO Administration:

    • Dilute 100microg in 2mL with 8mL NaCl 0.9% to produce 10microg/1mL
     Weight-based Calculations
    IN Fentanyl
    Presentation: 450mcg:1.5mL
    Loading dose:  in
    Subsequent dose:  in
    IV Fentanyl Citrate
    Presentation: 100mcg:10mL
    < 70 years old: Loading dose  to  in  to 
    ≥ 70 years old or frail: Loading dose  in
    Subsequent dose:  in
    IV Fentanyl for Rapid Sequence Induction
    Presentation: /mL
    Calculated dose:  in   to  in
    IV Fentanyl infusion to maintain analgesia
    Presentation: /mL
    Calculated dose:  to  per hour ( to )

    • Ramped patients must not have loading doses administered - maintenance doses (maximum 25 microg) to effect as required.

    Adult < 70 years old:

    • Pre-hospital loading dose: titrate 1 microg/kg, slow push over 3-5 minutes (maximum single dose: 100 microg)
    • Subsequent dose: 25 microg to effect every 5 minutes, titrated to effect

    Adult > 70 years old or frail:

    • Pre-hospital loading dose: titrate 0.5 microg/kg slow push over 3-5 minutes (maximum single dose: 50 microg)
    • Subsequent dose: 25 microg to effect every 5 minutes, titrated to effect


    • Pre-hospital loading dose: titrate 0.5-1 microg/kg, slow push over 3-5 minutes (maximum single dose: 25 microg)
    • Subsequent dose: 1 microg/kg (up to 25 microg) every 5 minutes, titrated to effect
    WeightInitial DoseSubsequent at 5-10 minutesSubsequent IV Dose if required
    < 20 kg 1 x 0.05 mL
    (15 microg)
    1 x 0.05 mL
    (15 microg)
    Up to 1 microg/kg titrated to effect every 5 minutes
    (Maximum bolus dose 25 microg each time)
    21 - 30 kg 1 x 0.10 mL
    (30 microg)
    1 x 0.10 mL
    (30 microg)
    Up to 1 microg/kg titrated to effect every 5 minutes
    (Maximum bolus dose 25 microg each time).
    31 - 40 kg 1 x 0.15 mL
    (45 microg)
    1 x 0.15 mL
    (45 microg)
    Subsequent dose 25 microg titrated to effect every 5 minutes
    Small / elderly / frail 2 x 0.2 mL
    (120 microg)
    1 x 0.2 mL
    (60 microg)
    Subsequent dose 25 microg titrated to effect every 5 minutes
    Adult 3 x 0.2 mL
    (180 microg)
    1 x 0.2 mL
    (60 microg)
    Subsequent dose 25 microg titrated to effect every 5 minutes

    Subsequent IN dosages can be administered every 5-10minutes, titrated to effect.

    Critical Care


    • Loading dose: titrate 1 microg/kg, slow push over 3-5 minutes (maximum single dose - 100 microg)
    • Subsequent dose: 25-50 microg every 5 minutes, titrated to effect

    Infusion to maintain analgesia:

    Adult & Paediatric:

    • 1 to 2 microg/kg/hr, commencing at 1 microg/kg/hr
    • Use 500 microg in 10 mL ampoule and 40 mL sodium chloride 0.9% to create a solution with a concentration of 500 microg in 50 mL (10 microg/mL)

    Rate of infusion for syringe driver

    Dose20 kg30 kg40 kg50 kg60 kg70 kg80 kg90 kg100 kg
    1 microg/kg/hr 2 mL/hr3 mL/hr4 mL/hr5 mL/hr6 mL/hr7 mL/hr8 mL/hr9 mL/hr10 mL/hr
    2 microg/kg/hr 4 mL/hr6 mL/hr8 mL/hr10 mL/hr12 mL/hr14 mL/hr16 mL/hr18 mL/hr20 mL/hr
    Rapid Sequence Induction


    • 1- 3 microg/kg IV, slow push over 3-5 minutes


    • 1 microg/kg IV, slow push over 3-5 minutes
     Special Considerations
    • Adopt a low threshold to engage with the ED team if pain remains difficult to control
    • Drowsiness
    • Nausea/vomiting
    • Respiratory depression; monitor pulse oximetry for all patients having IV / IN Fentanyl
    • Cardiovascular effects:
      • Bradycardia
      • Hypotension (rare)

    Intranasal administration:

    • 450 microg/1.5mL

    Intravenous/intraosseous administration:

    • 100 microg/2 mL
    • 500 microg/10 mL

    Intravenous Fentanyl


    Current mode:
    Extended Care:
    Colour assist:

    Discarding unused medication must be witnessed and countersigned by attendant and credible witness.


    Document Control

    Clinical Services

    Responsible Manager
    Head of Clinical Services


    Issue Date

    Expiry Date

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