Exposure to methoxyflurane: Low-dose analgesia and occupational exposure


emergency medical services

How to Cite

Allison SJ, Docherty PD, Pons D, Chase JG. Exposure to methoxyflurane: Low-dose analgesia and occupational exposure. Australasian Journal of Paramedicine [Internet]. 2020May11 [cited 2021Nov.28];17. Available from: https://ajp.paramedics.org/index.php/ajp/article/view/712



Evidence of nephrotoxicity led to abandonment of methoxyflurane anaesthesia. In lower doses via the Penthrox® inhaler, methoxyflurane is used for analgesia. We aim to review the literature to identify the relevance of methoxyflurane as an effective analgesic agent, identify whether there are any patient safety concerns in modern use, and determine occupational risk to healthcare personnel due to environmental methoxyflurane exposure.


Articles were located via PubMed, ScienceDirect, Google Scholar, Anaesthesiology and the Cochrane Library.


Single low-dose exposure to methoxyflurane may elevate blood fluoride levels below the toxic range, and appears relatively safe for patients. There is limited literature of occupational methoxyflurane exposure within modern parameters. Risks could include nephrotoxicity or hepatotoxicity.


The safety of occupational methoxyflurane exposure is yet to be proved. Further independent studies quantifying occupational exposure and monitoring the health of personnel exposed to methoxyflurane need to be undertaken to ensure safety.




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