(Generic versions may still be available.)


Fluothane (halothane, USP) is supplied as a liquid and is vaporized for use as an inhalation anesthetic. It is 2-bromo-2-chloro-1, 1, 1-trifluoro-ethane. C 2 HBrClF 3

The molecular weight is 197.38. The drug substance halothane molecule has an asymmetric carbon atom; the commercial product is a racemic mixture. Resolution of the mixture has not been reported.*

* Klaus Florey, editor, Analytical Profiles of Drug Substances, Vol. 1, page 127, (1972).

Halothane is miscible with alcohol, chloroform, ether, and other fat solvents.

The specific gravity is 1.872-1.877 at 20C, and the boiling point (range) is 49C-51C at 760 mm Hg. The vapor pressure is 243 mm Hg at 20C. The blood/gas coefficient is 2.5 at 37C, and the olive oil/water coefficient is 220 at 37C. Vapor concentrations within anesthetic range are nonirritating and have a pleasant odor.

Fluothane (halothane) is nonflammable, and its vapors mixed with oxygen in proportions from 0.5 to 50% (v/v) are not explosive.

Fluothane (halothane) does not decompose in contact with warm soda lime. When moisture is present, the vapor attacks aluminum, brass, and lead, but not copper. Rubber, some plastics, and similar materials are soluble in Fluothane (halothane) ; such materials will deteriorate rapidly in contact with Fluothane (halothane) vapor or liquid. Stability of Fluothane (halothane) is maintained by the addition of 0.01% thymol (w/w), up to 0.00025% ammonia (w/w).

Related Drugs Index: