• A narcotic analgesic acting on CNS by binding with opioid receptors
  • Also combines to cause respiratory depression, vasodilation, decreases gag reflex and slows AV node conduction

Onset & duration:

  • IM: Onset 5-10 minutes; Peak 20-30 minutes; Duration 1-2 hours
  • IV/IO: Onset 2-5 minutes; Peak 20 minutes; Duration 1-2 hours
  • Severe pain
  • Sedation to maintain intubation
  • Hypersensitivity to morphine or other opioids
  • Renal impairment / failure
  • Late second stage of labour
 Precautions / Notes
  • Reduce doses for elderly, frail and low body weight patients
  • Hypotension, shock
  • Patient with respiratory depression, severe COPD
  • Respiratory tract burns
  • Patients on monoamine oxidase inhibitor
  • Patients with severe hepatic impairment
  • For IV injection, dilute 15mg/1mL with 14mL water for injection to make 15mg/15mL (1mg/mL), and inject slowly over 4-5 minutes.
 Weight-based Calculations
IM Morphine for analgesia
Presentation: /mL
Calculated dose:  to  in  to
IV Morphine for analgesia
Presentation: /mL
Calculated dose:  to  in  to
IV Morphine for sedation to maintain intubation
Presentation: /mL
Calculated dose:  to  ( to
Commence at 5mg/hr, titrate to effect.

Critical Care
Severe pain

Adult < 70 years:

  • IM: 5 – 10 mg
  • IV/IO: 2.5 – 5 mg
  • Repeat every 5 minutes. as needed, titrating to response

Adult > 70 years:

  • IM: 2 – 5 mg
  • IV/IO: 0.5 – 2.5 mg
  • Repeat every 5 minutes. as needed, titrating to response

    Paediatric > 1 year:

    • IM: 0.1 – 0.2 mg/kg, maximum dose 5 mg
    • IV/IO: 0.05 – 0.1 mg/kg, maximum bolus dose 2.5mg. Repeat dose every 5 minutes as needed, titrating to effect
    • Maximum dose 0.4 mg/kg
    • Do not exceed 20 mg
    Sedation to maintain intubation


    • 1 – 20 mg/hr IV/IO; consider co-administration with midazolam
    • Commence at 5 mg/Hr titrate to effect

    Paediatric > 1 year:

    • 0.01 – 0.04 mg/kg/hr IV/IO; consider co-administration with Midazolam.
    • Not to exceed adult doses above
     Special Considerations
    • Bradycardia
    • Hypotension
    • Drowsiness
    • Nausea and/or vomiting
    • Pinpoint pupils
    • Respiratory depression
    • Constipation

    15 mg in 1 mL ampoule

    Current mode:
    Extended Care:
    Colour assist:

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


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    Head of Clinical Services


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