The first results from the cannabis pilot trials in Zurich and Basel were recently published. Almost half of the participants in the pilot trial in Basel “Weed Care” continue to consume cannabis from illegal sources. The pilot trial in Zurich “Züri Can – Cannabis with Responsibility” is predominantly made up of men who consume cannabis on more than four days a week. You can find more current findings from the pilot trials in this article.

Interim results of the Basel study "Weed Care"

The “Weed Care” study has been running in the canton of Basel-Stadt for just over a year. Its aim is to investigate the controlled distribution of cannabis products. Of almost 700 interested people, 378 people were accepted for the study.

Participants can buy six different cannabis products from Swiss organic production in pharmacies. However, only 57 percent of participants are satisfied with the product range. More than half would like additional products such as edibles, THC oil or e-liquids.

Many participants continue to consume cannabis from illegal sources because they desire stronger products or other forms of consumption.

Despite access to legal cannabis products, no increase in consumption has been observed. A total of 2023 kilograms of cannabis have been sold since January 41. Participants consume on average about twenty days a month, with an amount of 1,2 grams per day. There were no significant incidents in the first year of the study.

The study is being conducted by the Basel Health Department, the University Psychiatric Clinics, the Aargau Psychiatric Services and the University of Basel. It will run until July 2025. Participants will be regularly questioned about their consumption habits and their physical and mental health. So far, 40 people have dropped out of the study.

Source: Basel study “Weed Care”: Participants consume on 20 days per month (bzbasel.ch)

First results of the study “Züri Can – Cannabis with responsibility”

The Website The University of Zurich offers a current overview of the status and initial results of the scientific study “Züri Can – Cannabis with Responsibility”. The analyses are published monthly by the Research Group on Addiction Disorders at the Psychiatric University Hospital Zurich.

The study began on March 22, 2023, when the first people began the enrollment process. Since August 22, 2023, study participants have been able to legally purchase study cannabis from their sources. According to the FOPH approval, the purchase of study cannabis is possible until October 2026.

Study participants can legally purchase THC-containing cannabis flowers (“grass”) or cannabis resin (“hashish”) from one of 21 outlets. This study examines three types of outlets with interventions to promote lower-risk cannabis use: pharmacies, the Drug Information Center (DIZ) of the City of Zurich, and cannabis social clubs.

Currently, 1928 people have been included in the study. A total of 2100 people can take part in the study. The participants are mostly male, and the 28 to 32 age group is most frequently represented.

The majority of study participants use cannabis four times a week or more. Participation in the study seems to be particularly attractive for people who use frequently, but people who use only a few times a month also participate.

About a quarter of the study participants showed signs of cannabis use disorder before accessing study cannabis. This was recorded by the Cannabis Use Disorder Identification Test (CUDIT). How this value develops is part of scientific research.

Study cannabis is purchased directly from the producers by the supply points. The range includes various products with different THC/CBD contents and genotypes. An overview of the products can be found on the Website the city of Zurich.

Since the start of sales, all products offered have been in demand by study participants; a total of around 16.500 sales have been made, resulting in the purchase of around 140 kg of cannabis.

What conclusions can be drawn?

The pilot projects provide the first important insights for an effective fight against the black market. It is clear that successful regulation of the cannabis market is only possible if the legislation adequately takes the needs of consumers into account.

It would not be productive to wait for the results of the first trials in three years and in the meantime hand the test subjects from the pilot trials back to the black market. It is therefore urgently necessary to find a permanent follow-up solution based on the results to date.

Position paper

The position of IG Hanf Schweiz on cannabis regulation can be viewed at the following link: Position paper on Swiss cannabis regulation – IG Hanf Schweiz / CANNABIS REGULATION SWITZERLAND – Implementation of the 10-point model “Protect and Control” – IG Hanf Schweiz

Further information on the “Züri Can” study and how to register can be found on the City of Zurich’s website “Züri Can – Cannabis with Responsibility”.

Website Züri Can (City of ZH): Züri Can – Cannabis with responsibility – City of Zurich (stadt-zuerich.ch)

Website current status (Uni ZH): Züri Can – Current status | Zurican | UZH