title: The effects of energy drink in combination with alcohol on performance and subjective awareness.
abstract: BACKGROUND
  This study investigated the coadministration of an energy drink with alcohol to study the effects on subjective intoxication and objective performance.
  
  
  OBJECTIVE
  This study aims to evaluate the objective and subjective effects of alcohol versus placebo at two alcohol doses, alone and in combination with an energy drink, in a balanced order, placebo-controlled, double-blind design.
  
  
  METHODS
  Two groups of ten healthy volunteers, mean (SD) age of 24 (6.5), participated in the study. One group consumed energy drink containing 80 mg of caffeine and the other consumed a placebo drink, with both receiving two alcohol doses (0.046 and 0.087% breathalyser alcohol concentration). Tests included breath alcohol assessment, objective measures of performance (reaction time, word memory and Stroop task) and subjective visual analogue mood scales.
  
  
  RESULTS
  Participants showed significantly impaired reaction time and memory after alcohol compared to the no alcohol condition and had poorer memory after the higher alcohol dose. Stroop performance was improved with the energy drink plus alcohol combination compared to the placebo drink plus alcohol combination. Participants felt significant subjective dose-related impairment after alcohol compared to no alcohol. Neither breath alcohol concentration nor the subjective measures showed a significant difference between the energy drink and the placebo energy drink when combined with alcohol.
  
  
  CONCLUSIONS
  Subjective effects reflected awareness of alcohol intoxication and sensitivity to increasing alcohol dose. There were no overall significant group differences for subjective measures between energy drink and placebo groups in the presence of alcohol and no evidence that the energy drink masked the subjective effects of alcohol at either dose.
authors.affiliation: Psychology Department, Faculty of Health and Life Sciences, University of the West of England, Frenchay Campus, Coldharbour Lane, Bristol, BS16 1QY, UK. chris.alford@uwe.ac.uk
authors.forename: Chris
authors.initials: C
authors.lastname: Alford
authors.forename: Jennifer
authors.initials: J
authors.lastname: Hamilton-Morris
authors.forename: Joris C
authors.initials: JC
authors.lastname: Verster
mesh_terms: D000328:Adult; D001364:Awareness / Q000187:drug effects*; D002110:Caffeine / Q000494:pharmacology; D004311:Double-Blind Method; D061215:Energy Drinks; D000431:Ethanol / Q000633:toxicity*; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000187:drug effects; D011597:Psychomotor Performance / Q000187:drug effects*; D011930:Reaction Time / Q000187:drug effects
chemical_list: D002110:Caffeine; D000431:Ethanol