Medical cannabis has been legal in the UK since 2018, accessible through...

https://smart-wiki.win/index.php/Can_I_get_a_medical_cannabis_prescription_in_the_UK_if_I%27m_a_runner%3F

Medical cannabis has been legal in the UK since 2018, accessible through specialist private clinics. Eligibility depends on your condition and history of failed treatments. Competitive runners should note that THC remains banned by WADA in-competition.