There’s no official government medical cannabis card in the UK. Access depends...

https://tango-wiki.win/index.php/What_Counts_as_Trying_Conventional_Treatments_Before_Medical_Cannabis%3F

There’s no official government medical cannabis card in the UK. Access depends on a specialist consultation and your clinical records. If you receive a prescription, private patient cards are available as optional, handy proof of your legal status.