Medical cannabis has been legal in the UK since 2018 when accessed through...

https://brooksiwjk610.wpsuo.com/the-competitive-runner-s-guide-to-medical-cannabis-navigating-legality-and-anti-doping

Medical cannabis has been legal in the UK since 2018 when accessed through specialist private clinics. Eligibility usually requires a chronic condition and proof that previous treatments were unsuccessful. It is a heavily regulated process