Since November 2018, medical cannabis has been legal in the UK, provided it is...

https://victor-wiki.win/index.php/Medical_Cannabis_vs_Opioids:_Navigating_Chronic_Pain_Treatment_in_the_UK

Since November 2018, medical cannabis has been legal in the UK, provided it is prescribed by a specialist consultant. It is usually considered only when other established treatments haven't effectively managed your condition