Since 2018, medical cannabis has been a legal treatment option for insomnia in...

https://mike-wiki.win/index.php/What_Does_%27Specialist_Prescription%27_Mean_for_UK_Medical_Cannabis%3F

Since 2018, medical cannabis has been a legal treatment option for insomnia in the UK, provided it is managed via regulated specialist prescribing. It is typically considered only after conventional therapies haven't yielded the desired results