Cannabis self-administration in the human laboratory: a scoping review of ad libitum studies

Abstract

Cannabis self-administration studies may be helpful for identifying factors that influence cannabis consumption and subjective response to cannabis. Additionally, these paradigms could be useful for testing novel pharmacotherapies for cannabis use disorder. This scoping review aims to summarize the findings from existing ad libitum cannabis self-administration studies to determine what has been learned from these studies as well as their limitations. We examined studies that specifically examined cannabis smoking, focusing on subjective response and self-administration behavior (e.g., smoking topography). A systematic search was conducted using PubMed and Embase from inception to October 22, 2022. Our search strategy identified 26 studies (total N = 662, 79% male) that met our eligibility criteria. We found that tetrahydrocannabinol (THC) concentration significantly affected subjective response to cannabis in some but not all studies. In general, cannabis self-administration tended to be most intense at the beginning of the laboratory session and decreased in later parts of the session. There was limited data on cannabis self-administration in adults older than 55. Data on external validity and test-retest reliability were also limited. Addressing these limitations in future ad libitum cannabis self-administration studies could lead to more valid and generalizable paradigms, which in turn could be used to improve our understanding of cannabis use patterns and to help guide medication development for cannabis use disorder.

Neuromodulation for Cannabis Use: A Scoping Review

“…In the only two studies that investigated multiple sessions of rTMS for the treatment CUD, only 2 of the 22 participants were women. This makes it difficult to extrapolate whether rTMS could be effective at reducing cannabis consumption in women, especially given important sex-related considerations (e.g., anatomical differences, hormonal differences) that could affect response to rTMS treatment [46] and some evidence from human laboratory studies that women may consume and respond to cannabis differently than men [47]. Trends in high school students suggest that females may be starting to use cannabis at higher rates than males, so it will be increasingly important to balance future studies by gender [48,49].…”