Halothane

Halothane vapour is an inhalational general anaesthetic. Its systematic name is 2-Bromo-2-chloro-1,1,1-trifluoroethane.

Once widely used as general anaesthetic, it has largely been replaced by sevoflurane and isoflurane for human use. Halothane is still widely used in veterinary surgery and the third world because of its lower cost.

Halothane rarely showed any ill effects when used once on a patient. However, after multiple exposure to halothane, there was increasing risk of developing severe liver damage. This was due to the small fraction of the vapour being metabolised to neoantigens. This rarely triggered a fatal autoimmune reactions, "halothane hepatitis". The flurane descendants, enflurane and isoflurane, were developed largely with the aim to find anaesthetic vapours that would not metabolise.