Medical cannabis doesn't grant immunity on the road. You remain subject to the...

https://www.red-bookmarks.win/legally-prescribed-cannabis-doesn-t-exempt-you-from-road-safety-while-a

Medical cannabis doesn't grant immunity on the road. You remain subject to the 2mcg/L THC limit and DVLA fitness standards. While a medical defence exists, legality doesn’t replace responsibility. Being legal isn't the same as being unimpaired.