Since 2018, medical cannabis is legal in the UK via specialist private clinics....

https://www.deltabookmarks.win/medical-cannabis-has-been-legal-in-the-uk-since-2018-for-specific-conditions-1

Since 2018, medical cannabis is legal in the UK via specialist private clinics. Access requires proof of failed prior treatments. For runners, caution is vital. WADA strictly prohibits THC in-competition, and traces can linger in your system for weeks