Possible Effects of Energy Drink Ingestion on Perceived Alcohol Intoxication

Inclusion Criteria: * Healthy male volunteers * Able and willing to comply with the requirements of the study, confirmed by written informed consent * Aged 20 to 26 years * Within acceptable range for weight and body mass index (70-85 kg and 21 to 25 kg/m2) * At least 12-14 years of formal education * In good general health as determined by medical history and screening investigations (see below) * Taking no regular medication * No history of psychiatric disorders * Moderate alcohol consumption (less than 190.4 g/week) according to the Daily Drink questionnaire (Collins et a., 1985) * "sporadic" users of Energy Drinks (fewer than 10 cans of 250 ml in the last 6 months) * Confirmation that the general practitioner/primary care physician knows no reason that would prevent their participation * Similar in social and demographic data, similar quality of life * similar patterns of use of alcoholic beverages and Energy Drinks as well as quality of life (Martinez et al., 2000) * similar level of physical activity (physical activity questionnaire) (Baecke et al., 1982) Exclusion Criteria: * Any condition that the investigator and/or sponsor consider might increase the risk to the volunteer or decrease the chance of obtaining satisfactory data * Consumed 2\>x\>4 caffeine-containing drinks/day within 3 months of screening * Smoked \>10 cigarettes/day or equivalent within 3 months of screening * Consumed more than 190.4 g alcohol per week, or have a history of alcohol or drug abuse or * Consumed less than one alcoholic drink per week