Prescribed medical cannabis doesn’t exempt you from the 2mcg/L THC limit. While...

https://evpowered.co.uk/feature/medical-cannabis-and-uk-driving-laws-what-ev-owners-must-know/

Prescribed medical cannabis doesn’t exempt you from the 2mcg/L THC limit. While a medical defence exists, it’s not a blank cheque. You must meet DVLA fitness-to-drive standards, and remember: legal status isn’t a substitute for impairment-free driving