Can you get medical cannabis for epilepsy in the UK?

Epilepsy is where UK medical cannabis policy began — the 2018 law change followed the cases of two children with severe treatment-resistant epilepsy. It is also where the gap between what is licensed and what families hoped for remains widest.

Is epilepsy treated with medical cannabis in the UK?

Yes, in two specific syndromes, on the NHS. A purified cannabidiol liquid is licensed and NICE-recommended for seizures associated with Lennox–Gastaut syndrome and Dravet syndrome, taken alongside clobazam, in patients aged two and over, and started through a specialist epilepsy service. A further approval covers seizures associated with tuberous sclerosis complex.

Outside those syndromes the picture is very different. Treatment-resistant epilepsy of other types is assessed by private specialists case by case, and access to unlicensed whole-plant products through the NHS has remained rare despite the 2018 law change — a gap that has been the subject of sustained public and parliamentary attention.

Epilepsy is the one condition on this site where trying something unsupervised carries a risk of serious harm. Stopping or reducing anti-seizure medication without specialist supervision can cause status epilepticus, which is life-threatening. Never do it.

What the evidence actually shows

Epilepsy has the best evidence of any condition here, and it is specifically evidence about purified cannabidiol in severe childhood syndromes. It does not generalise to epilepsy in general, and it does not generalise to products containing THC.

The pivotal trial, published in the New England Journal of Medicine, randomised 120 children and young adults with Dravet syndrome and drug-resistant seizures to cannabidiol oral solution at 20 mg/kg/day or placebo, added to their existing treatment. Convulsive seizure frequency fell from a median of 12.4 to 5.9 per month on cannabidiol, against 14.9 to 14.1 on placebo. Forty-three per cent of the cannabidiol group had at least a 50% reduction in convulsive seizures, against 27% on placebo. Adverse events included diarrhoea, somnolence, reduced appetite and raised liver enzymes; more participants withdrew from the cannabidiol group.

That is a proper randomised trial with a clear result — which is exactly why this use is licensed and most others are not.

What a specialist will want to see

There is no UK list of qualifying conditions, so nothing here entitles you to a prescription. A specialist works through your history and decides whether a monitored trial is justified for you. For epilepsy they will typically look at:

• Your epilepsy syndrome and seizure types, and who confirmed the diagnosis
• Whether you or your child have Lennox–Gastaut, Dravet or tuberous sclerosis complex, which changes the route entirely
• Which anti-seizure medicines have been tried, at what doses, and why each was stopped
• Whether epilepsy surgery, vagus nerve stimulation or ketogenic diet have been considered
• Whether a specialist epilepsy service is already involved — for the licensed indications, that is the NHS route
• Interactions, particularly with clobazam and valproate, which are clinically significant

The general requirements — age, a documented diagnosis, the convention that two standard treatments have been tried, and access to your medical records — are covered in What are the requirements?

Risks and reasons a specialist may say no

Cannabidiol interacts with other anti-seizure medicines in ways that matter. It raises levels of the active metabolite of clobazam and can raise valproate-related liver enzymes, which is why treatment requires specialist supervision and blood monitoring rather than a prescription and goodbye.

Reported side effects in the trials include diarrhoea, somnolence, reduced appetite, fatigue and raised liver enzymes. THC is a separate question: it is not the compound with the trial evidence in epilepsy, and specialists approach THC-containing products in people with epilepsy cautiously. The overriding rule remains that existing anti-seizure treatment continues unless a specialist changes it.

If you want to take this further

The useful next step is a proper assessment, not a better list. Gather your diagnosis, the treatments you have already tried and what happened with each, and your current medicines — that is what a specialist needs in order to give you a straight answer.

The consultation itself, and what happens after it, is set out in What is the process to get a medical cannabis prescription? If epilepsy is not the only thing you are being treated for, say so early: other conditions and other medicines change the assessment.

Patient guide · Written by the Flora House editorial team · Last reviewed: 31 August 2026