The consumption of alcohol associated with THC increases the high significantly

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What does the mixture of alcohol and cannabis in the body

The consumption of alcohol in combination with THC, even in small amounts, significantly increases the concentration of THC in the blood and therefore its level of psychoactive effect according to this new study.

Potential pharmacokinetic interactions are poorly understood. Here, this study tests the arrangement of vaporized cannabinoids in the blood and plasma (the liquid part of the blood in which the other major components of the blood are bathed), with and without alcohol at low oral simultaneous dose.

The study was conducted by researchers at Baltimore University and the University of Iowa School of Medicine, in conjunction with the US National Institute for Drug Abuse Research, which provided cannabis for the study.


32 adult smokers drank a placebo or low dose 10 alcohol min before inhaling 500 mg placebo and / or a low dose (2,9%) of THC was a higher dose (6,7%) THC vaporized. In all 6 individual alcohol-cannabis combinations. Blood and plasma were analyzed before and up to 8,3 hours after ingestion.

In total, 1 324 blood samples and 1 327 plasma samples were taken.

Unlike previous research in which participants are divided into different groups, this is a study based on experience, which means that each participant participated in each of the experimental conditions with a break of at least one week between conditions.

The advantage of such research is that it removes interpersonal differences between subjects because the comparison is done within the same group.


The pharmacokinetic parameters of the participating 19 blood and plasma are presented in the following documents.

The important interactions between alcohol and cannabis were:

  • When alcohol was co-administered with cannabis, THC, 11-OH-THC and CBN were significantly higher in the blood.
  • In plasma, alcohol significantly increased THC, 11-OH-THC, CBN and CBD.
  • THC doses after 8,3 hours were significantly higher than placebo
  • Plasma observations were similar to blood based on dose differences within the same individual at the time of collection.
  • There was no significant difference between cannabinoids in blood or plasma at any given time.

The researchers suggest that these results could explain the conclusions of previous studies conducted by the US Department of Transportation, according to which the impact of the cannabis / alcohol combination on driving is much more serious than cannabis alone and slightly more serious than alcohol alone.

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