Methoxyflurane (Penthrox®)



Penthrox® - "Green whistle"

Penthrox - green whistle
  • Methoxyflurane (C3H4Cl2F2O) is a volatile fluorinated hydrocarbon
  • Colourless liquid analgesic with a fruity odour
  • Highly lipophilic and rapidly absorbed via inhalation
  • Potentiated through GABA receptors & two-pore K+ channels
  • Metabolised in liver (CYP450 isozymes)
    • Metabolites include: Fluoride,  oxalic acid,di-fluoromethoxyacetic acid, di-chloroacetic acid
    • 60% excreted in urine: fluorine, fluoride & oxalic acid
    • Remainder is exhaled
    • Metabolites can cause renal damage at high concentrations



Content By Dr. Conor Deasy, Dr. Íomhar O' Sullivan 01/08/2016. Last review Dr. ÍOS 15/09/16.