Objective: The aim of this study was to determine whether the impacts of absinthe on attention performance and mood were different from those experienced with beverages that contain only alcohol. The ingredient causing absinthe's toxicity is believed to be thujone.

Method: A total of 25 healthy subjects participated in the study. An attention performance test and two questionnaires testing different mood dimensions were used. Three drinks with an identical amount of alcohol but with different amounts of thujone were offered.

Results: The results of the present study showed that the simultaneous administration of alcohol containing a high concentration of thujone had a negative effect on attention performance. Under this condition, the subjects tended to direct their attention to signals in the central field of attention and to neglect peripheral signals; the number of correct reactions decreased significantly in the peripheral field of attention, and reaction time and the number of "false alarm" reactions increased significantly. The effects were most prominent at the time of the first measurement. When the subjects were under the influence of alcohol or were administered both alcohol and a low thujone concentration, these effects were not observed. The assessment of mood state dimensions showed that the anxiolytic effect of alcohol was temporarily counteracted by a high thujone concentration.

Conclusions: As they are apparently opposed to the effect of alcohol, the reactions observed here can be explained by the antagonistic effect of thujone on the gamma-aminobutyric acid receptor. Similar alterations were observed for the other mood state dimensions examined.