Commentary on Lorenzetti et al.: The International Cannabis Toolkit (iCannToolkit)

The International Cannabis Toolkit (iCannToolkit) was recently proposed to address the need for universally accepted standards to measure cannabis exposure [1]. The iCannToolkit is a three-tier hierarchical framework of measurement tools that consolidates input from global leaders in cannabis research. The iCannToolkit is a promising step towards standardizing the quantification of cannabis exposure, albeit its limitations, as conceded by its developers [1]. The iCannToolkit's potential utility is primarily undermined by (1) the lack of consensus on a standard unit of cannabis and (2) ambiguity in rationale for measures on therapeutic versus ‘risky’ use of cannabis. The ways to address these areas for improvement are described below. What constitutes ‘safe’ cannabis exposure? Without agreement on a standard unit of cannabis, it is challenging to define and measure therapeutic and problematic cannabis exposure. The fundamental differences in tools that quantify cannabis exposure reflect (1) the diversity of cannabis products and methods of administration and (2) the widespread variation in the way researchers conceptualize a standard single unit of cannabis [2, 3]. In 2019, there was a proposal to define a standard tetrahydrocannabinol (THC) unit as 5 mg of THC, irrespective of the product type or administration [3]. In 2021, this proposal gained the support of several US organizations, including the National Institute on Drug Abuse, despite (1) the potential limitation of its feasibility to legal markets with appropriate product labeling and (2) the administration-based variation in THC effects [2, 4]. This definitional debate has important implications for the iCannToolkit's universal measures and self-report measures [1]. Without adoption of a viable standard, only within-subject comparisons of cannabis exposure and effects can reliably be made [2]. The iCannToolkit portrays biological assessment as the gold standard for measuring cannabis exposure. However, biological assessments are insufficient to identify patterns of cannabis exposure or potency of cannabis products administered through different methods [2]. These assessments are further complicated by the hypothesized ‘entourage effect’ of cannabis, through which the effect of the active ingredients of cannabis differs from the effect of the cannabis plant [5, 6]. To meaningfully characterize the impact of cannabis on how one functions or feels, biological assessments should be coupled with the self-report measures of the iCannToolkit hierarchy [1]. Additionally, within the rationale for the iCannToolkit, there is an emphasis on the identification of harmful use rather than therapeutic effects; this mirrors the funding trends for cannabis research [7]. The preference for certain measurement tools differs for researchers identifying the therapeutic effects of cannabis (i.e. the minimum amount needed for a favorable effect) rather than the harmful effects of cannabis (i.e. the maximum amount that can be considered safe). The iCannToolkit should challenge social norms through greater acknowledgment of the potential benefits of cannabis to pave the way for research in its therapeutic effects. In conclusion, the iCannToolkit has potential to enhance integration of evidence on cannabis exposure. Candid discourse on definitions and prioritization of outcomes is a necessary next step to refining the iCannToolkit. None. None.