Cannabis in its raw form is not recognised as having any medicinal purposes, and as such, I understand that the UK Government has no plans to legalise it for medicinal use. However, as you point out, Sativex, a cannabis-derived product, is a medically licensed product that can be helpful for people with multiple sclerosis.
Healthcare in Scotland is a devolved issue, and therefore it is for the Scottish Medicines Consortium to decide whether to make Sativex available on the NHS in Scotland, based on an assessment of the available evidence.