What Medical Cannabis Is

"Medical cannabis" is an umbrella term for cannabis and cannabis-derived products used to treat a medical condition under a doctor's supervision, rather than for recreation. The formal name in the UK is a mouthful. It's cannabis-based products for medicinal use, or CBPMs. The idea is simple though: it's the same plant, and the same active compounds, taken for a medical reason, on a prescription, in a known dose. That last part is what really separates it from the cannabis sold on the street.

Medical vs recreational: the real difference

It's tempting to think medical cannabis is a different, gentler kind of plant. Mostly, it isn't. The active ingredients, chiefly THC and CBD, are the same molecules whether the plant is grown for a dispensary or a dealer. What changes is everything around the plant:

A medical product is grown to pharmaceutical standards, lab-tested, and sold with a label that tells you exactly how much THC and CBD it contains. A doctor decides whether it's appropriate, sets a starting dose, and reviews how you respond. None of that is true of illegal-market cannabis. As we cover in What Cannabis Is, you can't know the potency, the contents, or what else might be in it. The medical route is, in effect, the regulated version of a product that is otherwise completely unregulated.

That doesn't make medical cannabis risk-free, and it doesn't mean it works for everything people hope it will. Those are the honest questions we get into on What It Treats & The Evidence. It just means the medical setting removes the biggest unknowns of the illegal one.

Licensed vs unlicensed: the distinction that matters most

Within medical cannabis there's a second split that trips almost everyone up, and it's worth getting straight. There are two categories of product, and they are not the same thing.

Licensed medicines are the small number of cannabis-based products that have been through full clinical trials for a specific condition and been formally approved by a medicines regulator. There are three in the UK. STRONG

Unlicensed products are everything else: the whole-flower and cannabis-oil products that most people actually picture when they hear "medical cannabis". These haven't been through that full trial-and-approval process for the conditions they're used for. A specialist can still prescribe them for an individual patient (a "named-patient" or "special" prescription), most commonly for chronic pain, anxiety and some neurological conditions. But "unlicensed" carries real weight. It means the formal evidence bar hasn't been cleared for that use, and the prescription reflects one specialist's judgement rather than a settled proof that the product works for that condition in general.

We keep coming back to this split because it explains a lot, including why access is so uneven, and why two people can both say they're "on medical cannabis" and mean very different things.

Where it came from in the UK

Cannabis has a long medical history, but its modern UK medical route is recent. After a run of high-profile cases involving children with severe epilepsy, the law changed on 1 November 2018 to let specialist doctors prescribe CBPMs. Crucially, that did not legalise cannabis generally. Recreational use, possession and supply remain Class B offences. The full picture of who can prescribe, how you actually access it, and how it works in other countries is on The Law Around the World.

One last framing before the detail pages: this section is here to explain medical cannabis, not to steer you toward it. Whether a CBPM is right for a particular person is a decision for that person and a specialist doctor. It's never something to act on from a website, this one included.