Regulated Cannabis Access in Basel
September 1, 2026 updated by: Marc Walter, Health Department of the Canton of Basel-Stadt
WEED CARE - Randomized Controlled Study on Regulated Cannabis Access for Recreational Use in Pharmacies in Basel
The randomised controlled study on regulated cannabis access in pharmacies in Basel aims to investigate the effects of regulated cannabis access on consumption behaviour and mental and physical health in comparison to the illegal market.
Study Overview
Status
Active, not recruiting
Intervention / Treatment
Detailed Description
This project consist of two parts: The first part is a randomised controlled study, the second part is an observational study.
The randomised controlled study will last six months.
Participants will randomly be assigned to one of two groups: Group 1 has immediately access to regulated cannabis in pharmacies; Group 2 has to wait for six months.
After six months all participants will have access to regulated cannabis in pharmacies (oberservational study).
Every six month participants will be invited to answer online-questionnaires on their cannabis consumption behavior, their mental and physical health.
The entire study lasts 2.5 years.
Study Type
Interventional
Enrollment (Actual)
374
Phase
- Not Applicable
Contacts and Locations
This section provides the contact details for those conducting the study, and information on where this study is being conducted.
Study Locations
-
-
Canton of Basel-City
-
Basel, Canton of Basel-City, Switzerland
- Canton Basel-Stadt
-
-
Participation Criteria
Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.
Eligibility Criteria
Ages Eligible for Study
18 years and older (Adult, Older Adult)
Accepts Healthy Volunteers
Yes
Description
Inclusion Criteria:
- At least 18 years, residence in Basel-Stadt, consuming cannabis at least monthly during the last 6 months (positive urine sample)
Exclusion Criteria:
- pregnant or breastfeeding, currently suicidal, currently psychotic, current inpatient psychiatric treatment
Study Plan
This section provides details of the study plan, including how the study is designed and what the study is measuring.
How is the study designed?
Design Details
- Primary Purpose: Other
- Allocation: Randomized
- Interventional Model: Parallel Assignment
- Masking: None (Open Label)
Arms and Interventions
Participant Group / Arm |
Intervention / Treatment |
|---|---|
|
Experimental: Experimental group
Immediately regulated cannabis access in pharmacies.
|
The study does not investigate the health effects of cannabis.
The study investigates the effects of regulated cannabis access on cannabis consumption and health in comparison to the unregulated illegal market.
|
|
No Intervention: Control group
During the first six months participants of the control group have to continue to buy their cannabis on the illicit market.
Afterthese six months they also have access to regulated cannabis access.
|
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Change in problematic cannabis consumption behaviour
Time Frame: 6 / 12 /18 /24 / 30 months
|
Cannabis Use Disorder Identification Test - Revised; min.
value 0, max.
value 32; higher scores mean worse outcome
|
6 / 12 /18 /24 / 30 months
|
Secondary Outcome Measures
Outcome Measure |
Measure Description |
Time Frame |
|---|---|---|
|
Change in depression
Time Frame: 6 / 12 /18 /24 / 30 months
|
Patient Health Questionnaire; min.
value 0, max.
value 27; higher scores mean worse outcome
|
6 / 12 /18 /24 / 30 months
|
|
Change in anxiety
Time Frame: 6 / 12 /18 /24 / 30months
|
Generalized Anxiety Disorder; min.
value 0, max.
value 21; higher scores mean worse outcome
|
6 / 12 /18 /24 / 30months
|
|
Change in psychosis
Time Frame: 6 / 12 /18 /24 / 30 months
|
Checklist of early intervention; min.
value 0, max.
value 8; higher scores mean worse outcome
|
6 / 12 /18 /24 / 30 months
|
|
Change in physical health
Time Frame: 6 / 12 /18 /24 / 30 months
|
Symptom Checklist - 90, Somatization; min.
value 0, max.
value 48; higher scores mean worse outcome
|
6 / 12 /18 /24 / 30 months
|
Collaborators and Investigators
This is where you will find people and organizations involved with this study.
Publications and helpful links
The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.
Study record dates
These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.
Study Major Dates
Study Start (Actual)
January 31, 2023
Primary Completion (Estimated)
January 31, 2027
Study Completion (Estimated)
January 31, 2027
Study Registration Dates
First Submitted
August 8, 2022
First Submitted That Met QC Criteria
August 29, 2022
First Posted (Actual)
August 30, 2022
Study Record Updates
Last Update Posted (Actual)
September 2, 2026
Last Update Submitted That Met QC Criteria
September 1, 2026
Last Verified
September 1, 2026
More Information
Terms related to this study
Additional Relevant MeSH Terms
Other Study ID Numbers
- 2021-01670
Plan for Individual participant data (IPD)
Plan to Share Individual Participant Data (IPD)?
YES
IPD Plan Description
All IPD that underlie results in publications.
IPD Sharing Time Frame
6 months after publication
IPD Sharing Access Criteria
Only research institutions will have access.
Data dictionaries will be shared for studies that are planning to investigate similar research questions.
Principal investigator or co-investigator will review the requests.
IPD Sharing Supporting Information Type
- SAP
- ICF
Drug and device information, study documents
Studies a U.S. FDA-regulated drug product
No
Studies a U.S. FDA-regulated device product
No
This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.