• Wafer onset: 3-10 minutes

Pharmacology Review

  • Rapid acting dissociative anaesthetic
  • IM onset: 5-10 minutes
  • IV onset: 1 minute
  • Use of a sedative agent should never be considered routine. Have a high threshold to offer or administer.

Pharmacology Review

  • IV: Second line agent for severe pain of traumatic origin post IV Fentanyl administration. ASMA consult needed if IV Fentanyl minimum dose (age dependent as per CPG) has not been given prior to IV Ketamine administration
  • IM: First line agent for severe pain of traumatic origin should other means of administering pain medication not be available
  • Combative Traumatic Brain Injury
  • Oral wafer: Second line agent for moderate to severe, acute onset pain in patients >12 years where first line agents have failed to provide adequate relief
Paramedic only
  • (RASS 4) First line agent for severely disturbed or abnormal behaviour where there is an immediate risk to safety and rapid tranquilisation is required and no other sedative medications have already been administered to this patient
  • Hypersensitivity
  • Active cardiovascular disease including cardiac chest pain, heart failure, severe or poorly controlled hypertension
  • Patients with delayed transfer of care (i.e. 'ramped')
  • Disturbed and abnormal behaviour that are clearly not RASS 4 or where other sedative agents have already been administered (ASMA authority required)
  • Rapid Tranquilsation ONLY: Age < 16 years old
  • Age < 1 years old
  • Oral wafer: Age <12 years old
 Precautions / Notes
  • Wafer can be administered to patients experiencing non-traumatic pain where methoxyflurane has proven to be ineffective or cannot be administered.
  • Prior to administration of the Ketamine Wafer, patients should be encouraged to rinse mouth with water and swallow completely.
  • Wafer should be placed posterior towards the base of the tongue and medially on either side of the frenulum in the sublingual space.
  • Caution in patients with stable psychiatric disorders such as Schizophrenia
  • Caution in patients with hyperthyroidism or receiving thyroid replacement due to increased risk of hypertension and tachycardia
  • Analgesia – IV Fentanyl minimum dose (age dependant as per CPG) should be given prior to IV Ketamine administration
  • Analgesia for Non traumatic pain (IM / IV / IO) in opioid-dependent patients – consider SOC CSP consult
Sedation warnings
  • Sedation is HIGH RISK – must only be carried out after careful deliberation between officers and must not be based primarily at the request or influence of other agencies on scene (e.g. Police etc.)
  • Positive RASS score does not automatically infer a need to sedate
  • Age <16 years old – sedation should prompt a prior ASMA consult wherever practicable
  • ETOH / Intoxication – apply caution
  • Repeat & Maintenance doses – have a low threshold to consult with ASMA where repeat or maintenance doses are required
  • Monitoring – SpO2 and EtCO2 monitoring must be applied whenever level of consciousness drops (~RASS -2 or below)
  • Positioning – DO NOT transport in supine position (increases risk of laryngospasm from secretions) – transport in lateral position
  • Airway & Breathing – monitor airway and breathing effort, including chest movement closely for signs of impairment. Prepare to support if required
  • Restraint – Prone and/or handcuffed to rear carries excessive risk and MUST NOT occur. Physical restraint in any position that amplifies the risk of positional asphyxia, must be closely observed for signs of air hunger and hypoxia
  • RASS scores must be agreed and documented
  • Weight – Estimated weight must be agreed before administration of any weight based medicines. This must be documented

The final decision to sedate lies with the most senior clinician on scene


Ketamine for IV / IO Administration:

  • Dilute 200 mg in 2 ml with 18 ml NaCl 0.9% to produce 10 mg/1 ml
 Weight-based Calculations

Select indication

IM Ketamine for Combative Traumatic Brain Injury
Presentation: 200mg:2mL (100mg/mL)
Calculated dose:  in
IV Ketamine for Combative Traumatic Brain Injury
Presentation: 200mg:20mL (10mg/mL)
Calculated dose:  in
IM Ketamine for Rapid Tranquilisation (RASS 4)
Presentation: 200mg:2mL (100mg/mL)
Over 16 years only:
Moderate to severe alcohol intoxication:  in 
Nil to mild alcohol intoxication:  in 
IV Ketamine for maintenance of Rapid Tranquilisation (RASS 4)
Presentation: 200mg:20mL (10mg/mL)
Over 16 years only:
Calculated dose:  in 
IM Ketamine for analgesia
Presentation: 200mg:2mL (100mg/mL)
Initial dose:  in
Repeat dose:  in
IV Ketamine for analgesia
Presentation: 200mg:20mL (10mg/mL)
Calculated dose:  to  in  to  in
Subsequent dose:  to  in  to 
Critical Care
IV Ketamine for Rapid Sequence Induction
Presentation: /mL
Calculated dose:  in
IV Ketamine infusion for Sedation
Presentation: /mL
Calculated dose:  to  ( to ) per hour.
IV Ketamine for IV/IO analgesia
Presentation: /mL
Calculated dose:  to  in  to .
Subsequent dose  to  in  to  at >3min intervals Repeat at >3min intervals
IV Ketamine for Procedural Analgesia
Presentation: /mL
Calculated dose:  in
Subsequent dose  in after 2 min with repeat doses >1min intervals until adequate sedation is achieved.
IV Ketamine infusion for Analgesia
Presentation: /mL
Calculated dose:  to  to

  • Oral Wafer:
    • Initial dose: 2x 25mg wafers (50mg total)
    • Subsequent doses at 5 minute intervals: 1x 25mg wafer
    • Administer up to 3x subsequent doses (max total administration: 125mg)
    • Contact CSPSOC if additional analgesia required
For Prehospital use only


  • IM (pre-hospital only):
    • Initial dose: 1 mg/kg
    • Subsequent doses at 5 minute intervals – 0.5 mg/kg
    • Concentration: 200 mg/2 ml = 100 mg/ml
  • IV/IO (pre-hospital only):
    • Initial dose: 5 - 20 mg titrated to effect over at least 1 minute
    • Subsequent doses at 5 minute intervals: 5 - 10 mg titrated to effect


  • IM (pre-hospital only):
    • Initial dose: 1 mg/kg;
    • Subsequent doses at 5 minute intervals: 0.5 mg/kg;
    • Concentration: 200 mg/2 ml = 100 mg/ml
  • IV/IO (pre-hospital only):
    • 0.1 mg/kg administered over at least 1 minute and titrated to effect
    • Repeat at 5 minute intervals as required
Rapid Tranquilisation (RASS 4)
For Prehospital use only

Administration limited to those with independent authority to practice per the Medications Schedule


Adult 16 or over 

  • Initial dose (agreed ideal body weight):
    • up to 2 mg/kg repeat if necessary to a maximum cumulative dose of 200 mg in moderate to severe alcohol intoxication OR
    • up to 4 mg/kg repeat if necessary to a maximum cumulative dose of 400 mg in nil to mild alcohol intoxication

Adequate sedation may be achieved with lower doses on a case-by-case basis

  • IV access obtained as soon as practicable:
    • ASMA consult required where IV access is not achieved and further sedation required.

IV for maintenance of ketamine-induced sedation only:

  • 0.5 mg/kg repeated every 5 - 10 minutes ONLY IF REQUIRED
Combative Traumatic Brain Injury (TBI)
For Prehospital use only


  • Initial dose: 2 mg/kg to a maximum of 200 mg (agreed ideal body weight)
  • IV access obtained as soon as practicable


  • 0.5 mg/kg repeated every 5-10 minutes IF REQUIRED
Critical Care Paramedic only

Adult (IV/IO):

  • Initial dose: 10-20 mg
  • Subsequent dose 10 -30 mg at > 3min intervals

Paediatric (IV/IO):

  • 12 months initial dose: 0.1-0.2 mg/kg.
  • Repeat >3min intervals
Procedural Analgesia


  • IM:
    • 2 mg/kg to a max of 200 mg
  • IV/IO:
    • Initial loading dose: up to 0.5 mg/kg
    • Subsequent dose 10 mg after 2 min
    • Further 10mg doses >1min intervals until adequate sedation is achieved.


  • IM:
    • As per analgesic dose
  • IV/IO:
    • Initial loading dose: 0.2 mg/kg
    • Subsequent dose 0.1 mg/kg after 2 min
    • Further 0.1 mg/kg doses >1min intervals until adequate sedation is achieved.
Rapid Sequence Induction

Adult/Paediatric Induction (RSI), IV/IO:

  • 2 mg/kg
  • 1 mg/kg if haemodynamically compromised


  • 0.25 mg/kg/hr – 1 mg/kg/hr; commence 0.5 mg/kg/hr
  • 200 mg in 2 ml dilute up to 50 ml NaCl 0.9%. (4 mg/ml)


  • 0.1 mg/kg/hr  - 0.5 mg/kg/hr Commence lower dose 0.2 mg/kg/hr
  • 200 mg in 2 ml dilute up to 50 ml NaCl 0.9%. (4 mg/ml)
  • Rate of infusion syringe driver (Ketamine)
0.1 mg/kg/hr 0.25 ml/hr0.5 ml/hr0.75 ml/hr1 ml/hr1.25 ml/hr1.5 ml/hr1.75 ml/hr2 ml/hr2.25 ml/hr2.5 ml/hr
0.2 mg/kg/hr 0.5 ml/hr1 ml/hr1.5 ml/hr2 ml/hr2.5 ml/hr3 ml/hr3.5 ml/hr4 ml/hr4.5 ml/hr5 ml/hr
0.25 mg/kg/hr 0.625 ml/hr1.25 ml/hr1.875 ml/hr2.5 ml/hr3.125 ml/hr3.75 ml/hr4.375 ml/hr5 ml/hr5.625 ml/hr6.25 ml/hr
0.5 mg/kg/hr 1.25 ml/hr2.5 ml/hr3.75 ml/hr5 ml/hr6.25 ml/hr7.5 ml/hr8.75 ml/hr10 ml/hr11.25 ml/hr12.5 ml/hr
1 mg/kg/hr2.5 ml/hr5 ml/hr7.5 ml/hr10 ml/hr12.5 ml/hr15 ml/hr17.5 ml/hr20 ml/hr22.5 ml/hr25 ml/hr
Finger Thoracostomy
  • 200 mg in 2mL
 Special Considerations
  • Blood pressure and pulse frequently elevated
  • Random purposeless movements, muscle twitching and rash are common
  • Hypersalivation
  • Emergence reactions (10%)
  • Transient laryngospasm
  • Transient apnoea or respiratory depression

Oral administration:
25 mg sublingual wafer

IV / IO / IM administration:
200 mg in 2 mL

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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