• To provide vapour inhaled analgesia to a patient who can self administer.
 Patient Factors & Considerations
  • Ensure sufficient ventilation when using the Penthrox inhaler, using the updated ventilation system where installed as per WISE04 instruction.
  • All relevant infection control methods to be utilised.
  • Prepare equipment required:
    • Methoxyflurane and Penthrox inhaler[1]
    • Charcoal filter
    • Resuscitation mask (if required)
  • Attach the charcoal filter to the diluter hole[2].
  • Hold the Penthrox inhaler at a 10 to 20° angle with the mouthpiece end pointing downwards.
  • Decant the medication slowly into the base surrounding the oxygen connection.
  • Gently roll the inhaler to ensure proper absorption of the medication.
  • Explain the procedure to the patient.

  • Hand the Penthrox inhaler to the patient whilst explaining all aspects of the medication.
  • Attach the strap to the patient’s wrist.
  • Instruct the patient to form a seal around the mouthpiece by pressing their lips together and breathing in and out through the inhaler[3].
  • To increase concentration the patient can block the dilutor hole on the carbon filter[4].
  • Do NOT attach inhaler to oxygen source.
  • On termination of administration place Penthrox inhaler into plastic bag, seal and discard[5].
  1. Medications - Penthrox1

  3. Medications - Penthrox2

  5. Medications - Penthrox3

  7. Medications - Penthrox4

  9. Medications - Penthrox5
  • Adequate analgesia as per Relief of Pain Clinical Practice Guideline.
  • If ineffective, consider alternatives or multimodal analgesia regime as per Relief of Pain Clinical Practice Guideline
  • See medication Clinical Practice Guideline.
Additional Information
  • Concurrent use of multiple pain relieving strategies, including pharmacological and non-pharmacological interventions provides superior pain relief when compared to any single approach to pain management alone.

Extended Care:
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Responsible Manager
Head of Clinical Services


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