Medical cannabis is legal, but driving isn't a free-for-all. Keep under the...

https://bizzmarkblog.com/the-motorists-guide-to-medical-cannabis-dvla-rules-section-5a-and-staying-legal/

Medical cannabis is legal, but driving isn't a free-for-all. Keep under the 2μg/L THC limit and maintain DVLA fitness. A medical defence exists, but legality doesn't replace personal responsibility: if you’re impaired, stay off the road.