• Indications and contraindications for use of PENTHROX

• Guideline on the practical use of PENTHROX

• PENTHROX is intended for use as a first-line analgesia in adults with moderate or severe trauma-related pain

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Print copies must be destroyed after use.

Abbreviations

• Trauma-related pain e.g., dislocations, fractures, open wounds and burn injuries

• Acute pain, i.e., not appropriate for acute on chronic or breakthrough pain

• Patient under the age of 18 years of age

• Known hypersensitivity to methoxyflurane

• Patients with history of malignant hyperthermia

• Patients with a history of previous use of PENTHROX resulting in liver damage

• Clinically evident renal disease

• Clinically evident cardio-respiratory instability

• Clinically evident respiratory depression

• PENTHROX should be used with caution in the elderly with known risk factors for renal disease and with conditions that might predispose to renal injury, e.g., long lie, concurrent sepsis

• PENTHROX should be used with caution in those with known liver disease

PENTHROX should be self-administered

It should be used under supervision of a person trained in its administration, using the handheld PENTHROX Inhaler.

It is inhaled through the custom-built PENTHROX inhaler.

One dose is one bottle of 3 ml PENTHROX administered as a single dose, using the device provided.

No more than 6 ml should be used in a single day

PENTHROX should not be used on consecutive days with the total weekly dose not exceeding 15ml (5 x 3ml).

Onset of pain relief is rapid and occurs after 6-10 inhalations.

Patients can titrate the amount of PENTHROX inhaled and should be instructed to inhale intermittently to achieve adequate analgesia.

Continuous inhalation of a bottle containing 3 ml provides analgesic relief for up to 25-30 minutes; intermittent inhalation may provide longer analgesic relief.

Patients should be advised to use the lowest possible dose to achieve pain relief.

The person trained in administering PENTHROX will provide and explain the Package Leaflet to the patient.

• Common reactions include CNS reactions, e.g., dizziness and headache.

• Most adverse effects are non-serious and reverse upon cessation of use.

Patient Alert Card

Are kept in the Omnicell.

Galen Limited (2025) PENTHROX 99.9%, 3 ml inhalation vapour, liquid. Available at: https://www.medicines.org.uk/emc/product/1939/smpc (Accessed: 28 April 2025).