Human Psychopharmacology Clinical and Experimental
June 1, 2006
Sean P. Barrett, Christine Darredeau, Robert O. Pihl
276 citations
Among 149 university students who use drugs, alcohol, tobacco, and cannabis are frequently used together and with other substances. When alcohol is taken with cannabis, psilocybin, MDMA, cocaine, amphetamine, methylphenidate, or LSD, alcohol is typically consumed first. People drink more alcohol when they also use cocaine or methylphenidate than when they drink alone. Tobacco smoking increases above usual rates when used with alcohol, cannabis, psilocybin, MDMA, cocaine, amphetamine, LSD, or methylphenidate. Cannabis use patterns do not systematically relate to other substances. The findings indicate that the way a substance is used often depends on what other substances are taken at the same time.
The Canadian Journal of Psychiatry
August 1, 2002
Samantha R. Gross, Sean P. Barrett, John S. Shestowsky et al.
97 citations
In a sample of 210 rave attendees in Montreal, alcohol and cannabis were the most commonly used substances, both over a lifetime and in the previous 30 days. MDMA and amphetamine were the next most popular drugs for recent use and for having ever tried. The sequence of first use followed a consistent order: alcohol, nicotine, cannabis, LSD, psilocybin, amphetamine, cocaine, MDMA, GHB, ephedrine, ketamine. Early alcohol or cannabis use was associated with earlier experimentation with all other drugs tried by more than a quarter of the sample. Drug consumption levels were substantial, especially for MDMA, amphetamine, cannabis, and alcohol, with little heroin use.
Drug and Alcohol Review
May 21, 2012
Janine V. Olthuis, Christine Darredeau, Sean P. Barrett
79 citations
Among 226 cannabis users, most first-time use of harder illicit drugs—including cocaine, amphetamines, MDMA, heroin, and hallucinogens—involved simultaneous use of other substances, with at least 75% of participants reporting co-administration. Alcohol, tobacco, or cannabis were the substances most often used alongside the new drug. First-time use of alcohol, tobacco, and cannabis itself showed less simultaneous polysubstance use. The findings suggest that episodes involving alcohol, tobacco, or cannabis may directly facilitate the initiation of new substance use, pointing to potential risk factors for substance use progression.
Human Psychopharmacology Clinical and Experimental
January 1, 2000
Sean P. Barrett, Jennifer Archambault, Marla Engelberg et al.
11 citations
In a retrospective study of 22 people who used lysergic acid diethylamide (LSD) or psilocybin, most reported that hallucinogens blocked or reduced the subjective effects of alcohol. Among those who combined LSD with alcohol, 86.7% reported a complete blockade of alcohol effects, and the rest reported a diminished response. For psilocybin combined with alcohol, 60% reported a partial antagonism of alcohol effects. LSD's antagonism was significantly greater than psilocybin's. The authors suggest LSD's effect on alcohol intoxication may involve interactions with serotonergic and/or dopaminergic receptor systems.