Medical cannabis has been legal in the UK since 2018 via specialist private...

https://list-wiki.win/index.php/Does_Medical_Cannabis_Help_with_Sleep_Disruption_During_Marathon_Training_Blocks%3F

Medical cannabis has been legal in the UK since 2018 via specialist private clinics. Access requires a diagnosis and failed prior treatments. If you are a competitive athlete, please be cautious. WADA strictly prohibits THC during competition periods