Background: Cannabis was rescheduled in the UK in November 2018 so that it can now be prescribed as a treatment for certain medical conditions. It is not yet known whether this has had an impact on peoples’ perception of its risk or on their recreational use of cannabis.

Methods: This study used data from longitudinal and cross-sectional components of an online survey investigating drug use and nightlife behaviours, comparing data before and after rescheduling of cannabis in November 2018. Participants’ awareness of the change in policy and its impact on cannabis use were assessed for participants in both the cross-sectional and longitudinal arms. The perception of the risk of recreational cannabis use, past 12-month use and use frequency were assessed pre- and post-policy change among the longitudinal sample.

Results: 414 longitudinal (57.3% response rate) and 2001 cross-sectional participants completed the online survey, resulting in a total sample size of 2415. Just over half the sample (53.5%) were aware of the change in policy to allow for the medical provision of cannabis, with almost 90% saying this would have no impact on their recreational and approximately 80% no impact on their medical use of cannabis, irrespective of prior awareness. No significant differences were found with respect to risk perception, past 12-month cannabis use, or use frequency pre- and post-policy change among the longitudinal sample.

Conclusions: Amongst a sample of young adults strongly in favour of the provision of medical cannabis and in belief of its therapeutic potential, just over half were aware of the change in policy in the UK to allow for its medical provision for certain conditions. This is potentially lower than might be expected and may indicate that a considerable proportion of people in the UK may be unaware of this policy change. The majority of participants stated that their recreational and medical use of cannabis would not be affected by this change in policy,