Chronic tolerance and sensitization to alcohol in sons of alcoholics.

In view of conflicting results concerning differences between sons of alcoholics and sons of nonalcoholics in response to a single alcohol challenge (with a given dose), we exposed these high and low risk groups to several sessions in which they drank alcohol at the same dose in order to measure the development of chronic tolerance or sensitization with repeated doses. Sons of alcoholics and sons of nonalcoholics received a moderate dose of alcohol (0.5 g/kg) in three sessions with alcohol, followed by a placebo session. Sons of alcoholics developed reverse tolerance or chronic sensitization to repeated dosings of alcohol in finger pulse amplitude, while sons of nonalcoholics did not. Sons of alcoholics failed to show chronic tolerance in skin conductance and finger temperature, while sons of alcoholics did show the development of tolerance. Sons of alcoholics demonstrated greater motor activity throughout the sessions, both before and after alcohol. These results indicate that high and low risk groups differ in terms of their developmental adaptation to alcohol, as well as in the temperamental trait of behavioral activity.