RecruitingNAINTERVENTIONAL

Online Brief Advice Intervention for Heavy Cannabis Users

This study is investigating if a brief online intervention can help people who use cannabis most days understand more about cannabis withdrawal and their cannabis use. Researchers will compare a short educational video about cannabis withdrawal, combined with personalised feedback, against a relaxation video. The goal is to see if the educational approach can increase awareness and insight into cannabis use among daily users. The study will involve at least 100 people aged 18 and over who use cannabis heavily, recruited online. Participants will spend about 10-15 minutes completing questionnaires and watching assigned videos. The main aim is to see if the educational video helps people become more aware of their cannabis use and withdrawal symptoms, potentially influencing their intention to make changes.

At a glance

Status

Recruiting

Phase

Sponsor

King's College London

Enrolment target

100

Start

16 Oct 2025

Estimated completion

01 Sep 2026

Cannabis User

What is this study about?

This research project is looking into a new way to help people who use cannabis regularly. The main idea is to see if a short online session can make a difference in how well daily cannabis users understand the effects of cannabis, particularly withdrawal symptoms, and how this affects their overall use. Many people might not fully realise they are experiencing withdrawal symptoms or how much their cannabis use impacts them.

The study will involve asking volunteers to watch either a short educational video about cannabis withdrawal or a relaxation video. Along with the educational video, participants will get some personalised feedback about their own experiences with cannabis withdrawal. By comparing these two groups, the researchers hope to find out if the educational video is more effective at increasing people's awareness and understanding of their cannabis use.

The results of this study could be really important. If this short online approach proves to be helpful in increasing awareness, it could lead to new ways of supporting people who want to understand their cannabis use better. While this study is short-term, a positive outcome could pave the way for future, longer-term studies to explore whether such interventions can lead to lasting changes in cannabis use.

Key takeaways

This study explores if a short online video can boost awareness about cannabis use and withdrawal.
It's for adults (18+) who use cannabis heavily and regularly.
Participation involves a brief online session (10-15 minutes).
You'll watch either an educational video or a relaxation video.
The goal is to see if increased awareness can lead to reflections on cannabis use.
No physical visits, medication, or long-term commitment required.

Who may be eligible?

To take part in this study, you need to be an adult, aged 18 or older. You should also use cannabis very regularly – this means at least 25 days each month, and at least 3.5 grams (about an eighth of an ounce) of cannabis per week. It's also important that you can understand and speak English well enough to participate in the online tasks.

You would not be able to join the study if you are currently prescribed medical cannabis by a doctor or another healthcare professional. Apart from that, if you meet the other criteria, you're likely eligible to participate.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 18 years old or older?
Do you use cannabis at least 25 days out of every month?
Do you use at least 3.5 grams (about an eighth of an ounce) of cannabis per week?
Can you understand and communicate well in English?
Are you NOT currently prescribed medical cannabis by a healthcare professional?

Answer every question to see your result.

What does participation involve?

If you decide to take part, you'll first complete a very short online screening questionnaire (about 1 minute) to check if you meet the study requirements. If you do, you'll then be randomly assigned to one of two groups. One group will watch a short educational video about cannabis withdrawal and receive some personalised feedback. The other group will watch a relaxation video and complete a mood questionnaire.

Before and after watching your assigned video, you'll answer some questions about your background, your substance use, and your awareness of cannabis use. The entire process, from start to finish, is expected to take a short amount of time, about 10 to 15 minutes, and will all be done online. There are no face-to-face visits, medication involved, or long-term follow-up required for this particular study; it's a one-off online session.

Potential risks and benefits

Taking part in this study is low risk. You might find some of the questions or the educational video make you think more deeply about your cannabis use, which could be an uncomfortable but potentially helpful experience for some people. There are no physical risks associated with this online study. A potential benefit is that participating might increase your awareness and understanding of cannabis withdrawal and your own cannabis use. This might help you reflect on your habits, which could be a positive step for some individuals. Remember, your participation is completely voluntary, and you have the right to withdraw from the study at any time without giving a reason.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

Denmark Hill
Verified postcode
London, United Kingdom· Recruiting

Common questions

What exactly is 'cannabis withdrawal'?

Cannabis withdrawal refers to the uncomfortable symptoms some people experience when they stop or reduce their cannabis use after using it regularly. These can include things like irritability, anxiety, sleep problems, or changes in appetite.

Will I have to stop using cannabis for this study?

No, this study does not ask you to stop using cannabis. It aims to increase your awareness about cannabis use and withdrawal, not to change your current habits.

Is my information kept private?

Yes, all the information you provide will be kept confidential and handled according to strict research ethics guidelines. Your personal details will not be shared.

What happens after the study is over?

After you complete the online session of about 10-15 minutes, your participation in this study is finished. There are no further requirements or follow-up appointments.

Is there any payment for taking part?

The information provided doesn't mention payment, but studies recruited through platforms like Prolific often offer a small compensation for your time. You would need to check the specific details on the recruitment platform.

How to find out more

Edward Chesney, MRCPsych

edward.chesney@kcl.ac.uk 02078365454 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.