Since 2018, medical cannabis has been a legal treatment option in the UK,...

https://wiki-nest.win/index.php/Is_it_true_you_need_documented_treatment_history_for_UK_medical_cannabis%3F

Since 2018, medical cannabis has been a legal treatment option in the UK, provided through regulated specialist clinics. It is typically considered only when conventional insomnia treatments have proved ineffective or unsuitable