Leaving a cannabis pilot trial or moving home: What to check in Switzerland

Leaving a Swiss cannabis pilot trial or moving home? Clarify participation, purchase eligibility and data separately, with a checklist and example message.

You are taking part in a cannabis pilot trial and want to leave. Or you are moving home and do not know whether you can keep buying from your usual outlet. Having registered once does not answer the question. You need your project’s current documents and a clear response from the responsible team. This guide explains what to ask, what to keep a record of and why research participation, cannabis purchases and data processing are three separate matters.

Leaving voluntarily, moving home and a trial ending are different

When you withdraw voluntarily, you want to end your own participation. Moving home may change an eligibility requirement even though you would like to continue. A scheduled ending concerns the project’s duration or your particular study phase. These events do not necessarily involve the same administrative steps.

Start by identifying your actual study, the organisation responsible and the version of the participant information that applies to you. An outlet account, association membership and consent to research may exist alongside one another. Be specific about what you want to end. Simply no longer using a customer account is not reliable confirmation that your research participation has also finished.

How to communicate a voluntary withdrawal

Research participation is voluntary. If you no longer want to continue, say so clearly. Look in your participant information for the designated contact and process. Do not let an assumed notice period for club membership stop you communicating your withdrawal from research. An administrative confirmation is useful, but should not be confused with needing permission to leave.

Ask for a short written response confirming the end of your participation and the next steps. Check whether a closing conversation is offered, how existing appointments will be handled and whether the dispensing outlet also needs to be told. Do not assume there is a uniform Swiss notice period or apply a deadline from another project. Missing a questionnaire is not necessarily a clear record of your intention to withdraw.

Participation requirements and responsibilities in a cannabis pilot trial

Moving home: check the study’s catchment area

Staying within the same canton does not automatically mean all requirements remain satisfied. Your project’s relevant area may be narrower. Equally, every address change should not automatically be described as a complete withdrawal. Give the planned move date and ask whether the new address meets the criteria and what confirmation is needed.

Distinguish purchasing from any continued participation in surveys. Ask whether and until when you may obtain products, and whether another part of the research follow-up can continue. An old QR code or a card that still appears valid does not settle this. Moving also does not automatically transfer you into another study: that project assesses eligibility, admission and any existing registration separately.

Comparing Switzerland’s cannabis pilot projects

Purchases, study cards and products you already hold

Ask specifically when your purchasing eligibility ends. Updating an address, returning a card and disabling an account may be separate administrative actions. If your eligibility is unclear, wait for clarification before further purchases rather than treating a functioning card as approval. The responsible team should also explain whether and how a card must be returned or deactivated.

If you still hold study products, explain your outstanding questions to the team. Ask which project rules and legal requirements apply after leaving, and whether there is a return procedure. This article does not give blanket permission to possess, use or transport products, nor does it order universal destruction. Do not pass products to other people. Moving home does not, in particular, authorise taking cannabis across an international border.

What happens to your data after withdrawal?

Ending participation, withdrawing consent and requesting data deletion are not identical. Distinguish contact details, purchase records, health information and research data already analysed. Ask which processing stops, which data will still be used or retained and on what basis. The word ‘deregistration’ alone does not promise immediate deletion of every record.

One concrete example: the published Züri Can participant information allows withdrawal without giving a reason and continued coded analysis of data already collected. Check the current version of your own documents for your situation. Coded data are not necessarily anonymous: if a key can still connect records to a person, that differs from identification no longer being possible. For a deletion request, ask for the outcome and the reasons for any exceptions.

Check club membership privacy separately

A trial ending does not guarantee continued supply

The end of a pilot trial is not the same as general legalisation. An announced extension, a new study phase and confirmed individual purchasing eligibility are different things too. Do not rely solely on an old end year or a political announcement. Ask your team for the timetable that applies to you and any new documents you need to complete.

Check whether there will be a final appointment, closing questionnaire or information about the results. Also ask whether the team plans further research contact and how you can communicate your preferences. The last day of purchasing and the end of all data processing need not be the same date. Try to obtain separate answers to each question.

Options afterwards, without confusing legal routes

Another pilot trial requires its own admission process. Medical treatment needs an individual assessment by a doctor; leaving a trial creates neither a prescription entitlement nor a reimbursement entitlement. Membership of a private club is not a permit to obtain THC either. Check the actual legal basis of each offer rather than inferring access from a name or a future announcement.

If you want not only to leave the trial but also to reduce or stop cannabis use, raise that with the team and ask about appropriate support. Administrative withdrawal and your personal consumption decision are separate questions. This guide recommends neither replacement purchases nor a particular quantity to use. If you have symptoms or are receiving prescribed treatment, plan the next steps with an appropriate professional.

Why club membership and pilot participation have different legal bases

Checklist and an example message to your study team

Have your participant information, consent form and recent messages ready. Give your participant number, if available, and explain why you are contacting the team. An initial enquiry does not require you to send an entire medical record or identity document unprompted. Ask for an appropriate channel if additional personal documents are needed.

The example below is an enquiry about moving home. If you have decided to leave, replace it with an explicit statement that you are withdrawing participation. If you only want information, avoid accidentally deregistering. Keep your message and the response so you can distinguish outstanding questions from confirmed steps.

• Have the project name, participant number and current documents ready.
• Distinguish voluntary withdrawal, an address change and the scheduled ending.
• Identify the responsible contact and any outlet that also needs informing.
• Clarify when purchasing eligibility ends and what happens to the card.
• Ask for specific instructions about remaining products; do not pass them on.
• Discuss further surveys, data use and retention separately.
• Keep written answers and confirmed dates.

Example: reporting a move and asking what changes

I am taking part in [study, participant number] and expect to move on [date] from [current municipality] to [new municipality]. Please explain whether I will still meet the participation and purchasing criteria, and what information you require. If my eligibility changes, when does that take effect, what should I do with my study card and what rules apply to products already purchased? Please also explain separately whether further surveys are planned and how my existing data will be handled.

Reviewed on 17 October 2026. General information, not individual legal advice or confirmation of purchasing eligibility. Your project’s current documents and instructions determine the actual procedure.