In the UK, medical cannabis prescriptions start with a specialist...

https://augustsniceblogs.timeforchangecounselling.com/can-i-bring-my-own-research-to-a-cannabis-specialist-appointment-or-is-that-annoying

In the UK, medical cannabis prescriptions start with a specialist assessment—usually through private clinics, as NHS prescriptions are very rare. If approved, the medicine comes from regulated pharmacies to ensure safety