Concurrent use of cocaine and alcohol is more potent and potentially more toxic than use of either alone--a multiple-dose study

Biol Psychiatry. 1998 Aug 15;44(4):250-9. doi: 10.1016/s0006-3223(97)00426-5.


Background: Simultaneous abuse of cocaine and alcohol is widespread and increasingly detected in patients seeking emergent care. This double-blind, randomized, within-subjects study used a paradigm more closely approximating practices of drug abusers to better understand the pathogenesis of cocaine-alcohol abuse.

Methods: Subjects meeting DSM-IV criteria for cocaine dependence and alcohol abuse participated in three drug administration sessions: four doses of intranasal cocaine (1 mg/kg every 30 min) with oral alcohol (1 g/kg) administered following the initial cocaine dose and a second dose (120 mg/kg) at 60 min calculated to maintain plasma alcohol concentration at approximately 100 mg/dL during cocaine administration; four doses of cocaine/placebo alcohol; four doses of cocaine placebo/alcohol. Pharmacokinetic, physiological, and behavioral effects were followed over 8 hours.

Results: Cocaine-alcohol produced greater euphoria and increased perception of well-being relative to cocaine. Heart rate significantly increased following cocaine-alcohol administration relative to either drug alone. Cocaine concentrations were greater following cocaine-alcohol administration. Cocaethylene had a longer halflife with increasing concentrations relative to cocaine at later time points.

Conclusions: Enhanced psychological effects during cocaine-alcohol abuse may encourage ingestion of larger amounts of these substances over time placing users at heightened risk for greater toxicity than with either drug alone.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Affect / drug effects
  • Alcohol-Related Disorders / complications
  • Alcohol-Related Disorders / physiopathology*
  • Alcohol-Related Disorders / psychology
  • Analysis of Variance
  • Area Under Curve
  • Behavior, Addictive / psychology
  • Blood Pressure / drug effects
  • Cocaine-Related Disorders / complications
  • Cocaine-Related Disorders / physiopathology*
  • Cocaine-Related Disorders / psychology
  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Drug Synergism
  • Female
  • Heart Rate / drug effects
  • Humans
  • Male
  • Reward
  • Time Factors