Since November 2018, medical cannabis has been legal in the UK via specialist...

https://mike-wiki.win/index.php/Is_Medical_Cannabis_a_First-Line_Treatment_in_the_UK%3F_Separating_Fact_from_Marketing

Since November 2018, medical cannabis has been legal in the UK via specialist prescription, usually after other treatments fail. While the pathway exists, NHS access is rare, so most patients use private clinics. Always speak to your GP first.