Effects of the calcium channel antagonist darodipine on ethanol withdrawal in rats

The effect of the dihydropyridine calcium channel antagonist, darodipine, on ethanol withdrawal syndrome was examined in rats made dependent on ethanol by repeated ethanol administration for six consecutive days. Chronic co-administration of darodipine prevented the severity of ethanol withdrawal signs in a dose-dependent fashion. By contrast, acute administration of darodipine during the ethanol withdrawal phase was ineffective in reversing the withdrawal symptoms. The results suggest that the presence of darodipine in the central nervous system during the adaptative responses to ethanol is necessary to reduce the severity of the withdrawal syndrome. They also provide further evidence for a potential clinical usefulness of dihydropyridine calcium channel blockers in treatment of ethanol withdrawal.