Sodium bromide and sodium valproate: effective suppressants of ethanol withdrawal reactions in mice.

Mice were made physically dependent on ethanol by a 3-day alcohol inhalation regimen, using pyrazole to stabilize blood ethanol concentrations. After withdrawal, convulsions elicited by handling were scored repeatedly for 30 hr as a measure of central nervous system hyperexcitability. Administration of sodium bromide, 0.2 to 2.0 g/kg i.p., suppressed the convulsions in a dose-related fashion. Bromide was effective at subsedative doses. However, bromide increased the postwithdrawal mortality. Bromide may act at chloride channels, as gamma-aminobutyric acid does. Valproate and its amide temporarily suppressed the withdrawal reaction at doses that caused some sedation. Muscimol and beta-alanine had no effect.