The effects of energy drinks alone and with alcohol on neuropsychological functioning

Hum Psychopharmacol. 2009 Aug;24(6):473-81. doi: 10.1002/hup.1045.


Objective: Caffeinated energy drinks-alone or with alcohol-are heavily marketed to young adults, many of whom believe that caffeine counteracts some negative effects of alcohol intoxication. While the effects of caffeine and alcohol have been widely investigated, few studies have examined neuropsychological performance after consumption of a beverage containing both ingredients.

Methods: In a double-blind, placebo-controlled design, 27 non-caffeine-deprived female participants were randomly assigned to consume a caffeinated energy drink alone, one containing alcohol, or a non-alcoholic, non-caffeinated control beverage. Pre- and post-test assessments were conducted using alternate forms of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS).

Results: Participants who consumed the energy drink plus alcohol evidenced significantly lower post-test performance on a global score of neuropsychological status. Specifically, deficits were found in both visuospatial/constructional and language performance scores. While participants who consumed the caffeinated beverage alone trended toward improved attention scores, neuropsychological status did not show meaningful changes from the pre- to post-test.

Conclusions: Consumption of an energy drink containing 6% alcohol by volume negatively influenced performance on a global measure of cognitive functioning.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Alcohol Drinking / adverse effects
  • Beverages
  • Caffeine / pharmacology*
  • Central Nervous System Depressants / adverse effects
  • Central Nervous System Depressants / pharmacology*
  • Central Nervous System Stimulants / pharmacology*
  • Double-Blind Method
  • Drug Interactions
  • Ethanol / adverse effects
  • Ethanol / pharmacology*
  • Female
  • Humans
  • Neuropsychological Tests
  • Young Adult


  • Central Nervous System Depressants
  • Central Nervous System Stimulants
  • Caffeine
  • Ethanol