After years of tireless campaigning from families of people living with severe epilepsy, the UK has finally seen progression in the legal status of medical cannabis. More and more patients are now reaping the therapeutic benefits of this plant in the wake of their pioneering effort. But nearly four years after this change, NHS prescriptions remain scarce and the majority of UK medical cannabis prescriptions must be obtained through private clinics.
Despite what lead researchers say, the NHS believes there is insufficient evidence to prescribe cannabis-based medicines to children and adults with severe epilepsy – unless they fit strict eligibility criteria. Here, leafie takes a look at the latest research. We get into the how and why of getting a medical cannabis prescription to manage seizures here in the UK.
Epilepsy: an overview
Epilepsy is a chronic neurological disease where patients experience recurrent and debilitating seizures. It tends to affect more vulnerable age groups, such as children and the elderly. In the UK, there are currently over 600,000 people living with epilepsy.
Although epilepsy affects 1 in every 100 of the population, seizures manifest themselves differently in every individual. They can vary in severity, depending on which areas of the brain are affected and whether or not consciousness is lost. If patients display a particular set of symptoms or triggers that are consistent with specific criteria, they receive an epilepsy syndrome diagnosis.
There has been very little progress in terms of identifying a generalised cure for epilepsy, and identifying effective treatment has proven to be a challenge. Due to the vast array of seizure types and syndromes, a “one size fits all” approach won’t be successful. As such, many patients require a personalised cocktail of drugs to manage their seizures.
The first approach to treatment on the NHS is anti-epileptic drugs (AEDs), which aim to alter brain activity so that the frequency of seizures is significantly reduced. Common AEDs include:
- Sodium valproate
- Carbamazepine
- Benzodiazepines e.g clonazapem
- Barbituates e.g phenobarbitone
Unfortunately, these drugs are hugely limited by their adverse effects and are ineffective in up to a third of all patients. There are over 60,000 children under the age of 18 living with epilepsy in the UK, 23,000 of whom do not respond to common AEDs. The need for alternative treatments is obvious.
Medical cannabis and epilepsy in the UK
On November 1st 2018, cannabis-based medicines were legalised in the UK. Doctors on the General Medical Councils (GMCs) specialist register are now permitted to prescribe cannabis to manage seizures in patients who do not respond to traditional AEDs.
Existing evidence largely comes from research into the effects of Epidiolex, an oral CBD isolate-based product (99% CBD, 0.1% THC), which has now been licensed for the treatment of Dravet syndrome and Lennox-Gastaut syndrome – two childhood epilepsy syndromes that are particularly resistant to current treatments.
Several randomised, double-blind, placebo-controlled trials – the “gold standard” of experimental design – have found that Epidiolex significantly reduces seizure frequency in children and young adults with Dravet and Lennox-Gastaut syndrome, with some patients even becoming seizure-free with treatment.
Though more limited, there is also evidence in favour of using whole-plant cannabis to manage seizures. One study, published in the journal BMJ Paediatrics Open in 2021, investigated the effects of whole-plant cannabis on ten participants with intractable epilepsy, who had previously failed to respond to Epidiolex and had tried an average of seven conventional epilepsy drugs. Researchers found that children treated with whole-plant medicinal cannabis products displayed an average 86% reduction in seizure frequency.
During a recent event hosted by Drug Science and Medcan Support at the House of Lords, researcher Dr Rayyan Zafar presented findings which indicate that medical cannabis has a 96% chance of significantly reducing seizures in children with severe epilepsy. Although more research using larger sample sizes is needed, these initial findings provide a reliable indication that cannabis-based medicines could be an effective alternative epilepsy treatment for many eligible patients.
How does it work?
Exactly how cannabis works to control seizures in epilepsy isn’t fully understood, but there are several theories. Its therapeutic properties are largely attributable to its two major cannabinoids, cannabidiol (CBD) and tetrahydrocannabinol (THC). These compounds can modulate and activate cannabinoid receptors in the endocannabinoid system (ECS), which then has widespread effects on signalling systems across the brain and body.
Several researchers have highlighted a link between seizures and the ECS, with endocannabinoids believed to play a role in inhibiting excessive excitement in the brain. Since seizures are often described as an “electrical storm” in the brain, the effects of cannabis on endocannabinoid levels are likely what induces its protective effects.
Ultimately, there is still far to go in terms of the research, but experts are cautiously optimistic. Stories from families show that medical cannabis is already saving lives, and the supporting clinical evidence is piling high.
Is cannabis a safe treatment for epilepsy?
There are some risks and side effects that come with using medical cannabis, as there are with any medication. Fortunately, adverse effects are rare with cannabis-based medicines, particularly in comparison to common AEDs. Unlike existing medications, cannabis also appears to improve quality of life. “There’s the comorbidities, depression, the lack of sleep, the anxiety,” says Dr Callie Seaman from Medcan Support. “Cannabis helps with all those symptoms, not just the seizure control.”
According to the NHS, common side effects of cannabis-based medicines include appetite changes, diarrhoea, nausea, mood changes, dizziness, and tiredness. It is important to note, however, that CBD – the primary compound in Epidiolex – has been shown to exhibit a greater safety profile than THC with fewer reported side effects. CBD also shows “a better defined anticonvulsant profile in animal models” and no abuse potential, according to a paper published in the Journal of Epilepsy Research.
The National Institute on Drug Abuse (NIDA) also warns that the long-term use of THC may have some negative effects on the cognitive development of children. The British Paediatric Neurology Association (BPNA) has, therefore, stated that non-licensed medicinal cannabis with higher levels of THC should only be considered for children who:
- Have epilepsy that does not respond to conventional licensed AEDs
- Have not responded to or are suitable for the ketogenic diet
- Who are not candidates for epilepsy surgery
Though “evidently, the benefits of medical cannabis for these patients far outweigh any associated risks,” say the authors of a 2021 paper published in Drug Science, Policy and Law.
How to access treatment
Very few people in the UK are likely to get an NHS prescription for medical cannabis. That said, the NHS will currently consider children and adults with rare, severe forms of epilepsy for the prescription of Epidiolex. This can be prescribed alongside clobazam to manage seizures caused by Lennox-Gastaut syndrome and Dravet syndrome in children, providing other first-line treatment has not been successful.
Despite this, eligible patients often face a lengthy waitlist for treatment whilst patients and their families apply for NHS funding via the Refractory Epilepsy Specialist Clinical Advisory Service (RESCAS). As a result, only those with the financial privilege of private medical treatment have quick access to medical cannabis.
A new initiative, pioneered by leading cannabis campaigner Charlotte Caldwell, aims to help families with children on the medical cannabis waitlist. Caldwell is calling for private cannabis companies to offer free treatment to families of children with refractory epilepsy on the waitlist, covering up to £6,000 worth of private prescription costs.
Costs will vary between clinics; consultations typically range between £50 and £200 and the average prescription is around £150-£250 per month. One study has even noted that families of patients with epilepsy are paying £874 per month for their prescriptions. Other initiatives, such as Project Twenty21, cap prescriptions at £150 per product per month for patients who participate in ongoing clinical studies.
You can apply for a medical cannabis prescription either with a UK cannabis clinic directly or through a GP. In the initial consultation, a doctor will look at the patient’s medical history and what medications they have tried in the past to assess them on an individual basis.
If you’re keen to learn more about the process of obtaining a UK medical cannabis prescription, either for you or a loved one, take a look at leafie’s extensive guide.
