Concurrent use of cocaine and alcohol is more potent and potentially more toxic than use of either alone--a multiple-dose study.
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.
Yale Psychiatric Institute, New Haven, Connecticut, USA.
E F
EF
McCance-Katz
T R
TR
Kosten
P
P
Jatlow
D000328:Adult; D000339:Affect / Q000187:drug effects; D019973:Alcohol-Related Disorders / Q000150:complications / Q000503:physiopathology* / Q000523:psychology; D000704:Analysis of Variance; D019540:Area Under Curve; D016739:Behavior, Addictive / Q000523:psychology; D001794:Blood Pressure / Q000187:drug effects; D019970:Cocaine-Related Disorders / Q000150:complications / Q000503:physiopathology* / Q000523:psychology; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004357:Drug Synergism; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D012201:Reward; D013997:Time Factors