[The influence of ethanol, dithiocarb, diethylmaleate and phenobarbital on the metabolic elimination of halothane in rats (author's transl)].

Rats exposed to halothane (100 ppm) in a closed allglass-system eliminate halothane from the atmosphere of this system with a half-life (t0.5) of 0.99 h. In 24 h-fasted rats t0.5 was prolonged to 1.24 h. A single oral load of 4.8 g/kg ethanol as well as a 15% ethanol solution instead of drinking water for 28 days did not alter the metabolic elimination of halothane. On the other hand, ethanol (4.8 g/kg p.o.) applied 5 min before exposure to halothane markedly prolonged t0.5 to 3.79 h. Pretreatment with phenobarbital (80 mg/kg i.p. for 4 days) shortened t0.5 significantly to 0.79 h. Inhibition of the mixed-function oxidase system by dithiocarb (100 mg/kg i.p.) or diethyl maleate (1 ml/kg i.p.) markedly prolonged t0.5 to 7.53 and 1.57 h. respectively. The observed modifications of the halothane metabolism may be of interest in relation to the problem of halothane-induced hepatotoxicity.