Prescribed cannabis is legal, but it’s a grey area on the road. Even with a...

https://wiki-view.win/index.php/What_Happens_If_I_Crash_and_THC_is_Found_in_My_Blood%3F

Prescribed cannabis is legal, but it’s a grey area on the road. Even with a prescription, exceeding the 2μg/L THC limit can be problematic. A medical defence exists, but you must still meet DVLA fitness to drive standards