3. Cannabis-related effects and harms: a scientific overview

Wednesday, 23 November, 2022 - 10:50 to 12:20


Cannabis is the illicit drug most widely available in Europe and concerns have been raised about harms related to its use. First, the potency of resin and herb available on the illicit is increasing, and products with high potency in THC might cause different types of harms than the products used some years ago.

Second, limited information is available on the impact of cannabis policy changes on the availability of cannabis and patterns of use. Patterns of use might change with regards to the frequency and quantity used but also the use of other products such as edibles, vaping. The objective of this presentation is to summarise evidence of associations and causality in cannabis-related effects and harms based on a scientific review of literature and monitoring data on prevalence, acute harm and treatment demand.

The project includes: a scientific overview of findings from studies in the area of cannabis-related effects and harms. This involves the identification and systematic review of major reviews and studies on the topic (up to 2021). This will take as a starting point other major reviews on this topic and build on these and EMCDDA monitoring data.

Findings will address the following themes: effects and harms associated with: acute toxicity and long-term harm; somatic, psychological, psychiatric, in utero/breast feeding/infant exposure, cannabis use disorder; correlation with alcohol and tobacco use and dependence; road traffic accidents, and social harm (including the harm linked to prosecution). A monitoring framework for cannabis related harms will be presented.

The work is ongoing and at Lisbon Addictions 2022 the outcomes of this project will be presented.


Presentation files

23 115 1050 Jakob Manthey.pdf513.48 KBDownload



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