Epilepsy and Medical Cannabis: A Comprehensive Overview
Epilepsy is a surprisingly common neurological condition, affecting approximately 1 in 23 residents of the UK. Characterised by abnormal brain activity, it presents with a range of symptoms including unexpected seizures, headaches, and impaired cognition and communication. There are numerous types of epilepsy, each with its own unique set of symptoms.
While many types of epilepsy involve seizures accompanied by loss of consciousness and physical manifestations such as twitching and convulsions, others may allow the person to remain conscious or semi-conscious while experiencing abnormal sensory perceptions.
Epilepsy can manifest in childhood or later in life following a head injury, illness, or for unknown reasons. Each case of epilepsy is unique, making it a complex condition to understand and manage.
Currently, there are more than twenty-five pharmaceutical medication options available for those with epilepsy to manage their symptoms. However, some patients experience severe side effects from these medications, and some continue to have breakthrough seizures, which occur when a person still experiences significant seizure activity despite being on antiepileptic medication.
In some cases, patients with severe forms of epilepsy have found success in taking cannabis-based medicinal products (CBMPs) to reduce the intensity and frequency of their seizures. Presently, the NHS prescribes CBMPs for only three conditions, including two rare types of treatment-resistant epilepsy. Private clinics, such as Releaf, can prescribe medical cannabis products for a much broader range of health issues.
What is Medical Cannabis?
The cannabis sativa L. plant boasts a rich history of recorded medical use dating back nearly five millennia. The earliest records of cannabis as a medicine are from 2732 BC, when the Chinese emperor Shen Nung (often referred to as the “father of Chinese medicine”) prescribed it for a variety of conditions, including gout, rheumatism, and malaria.
Today, the term “medical cannabis” refers to pharmaceutical-grade cannabis-based medicinal products (CBMPs) derived from the plant and intended for medical use. These products come in a wide variety of forms, including dried flowers, oils, capsules, extracts, and lotions, each offering different levels of active ingredient concentration (known as cannabinoids and terpenes).
Typically, CBMPs are extracted from the plant to create a concentrate with higher potency and improved bioavailability. The most common cannabinoids in CBMPs are tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is responsible for the psychoactive effects of cannabis, while CBD offers no intoxication regardless of dosage but provides therapeutic benefits.
Thanks to a rapidly growing body of research, the medical applications of cannabis and its compounds are becoming increasingly clear. Research from around the world has shown that CBMPs can effectively treat numerous medical conditions, with epilepsy being one of the first conditions identified as benefiting from medicinal cannabis.
How Does Medical Cannabis Interact with the Body?
The human body has its own endocannabinoid system (ECS), identified in the late 1980s, which is the largest neurotransmitter system in the body. It regulates a wide range of bodily functions, including appetite, sleep, pain and inflammation, memory, and mood. Modern science suggests it acts as the body’s “master regulator”. CBMPs and their compounds interact directly with the ECS, enhancing the function of naturally occurring endocannabinoids.
When administered, CBMPs interact with cannabinoid receptors throughout the body and brain. These receptors are part of the ECS network, which allows cannabinoids to bind and activate them, triggering physiological responses and psychological effects. The two ECS receptors are CB1, located mostly in the brain and central nervous system, and CB2, found in peripheral organs and in high concentrations in immune cells.
THC has a strong affinity for CB1 receptors (and a weaker action on CB2), while CBD has a higher affinity for CB2 receptors and can reduce the enzymatic breakdown of endocannabinoids. Both cannabinoids also interact with other receptors, including serotonin, dopamine, vanilloid, opioid, and adenosine.
These interactions result in various therapeutic effects, including reduced inflammation and pain, decreased anxiety and improved mood, better sleep quality, and anticonvulsant properties. This makes CBMPs an attractive option for treating many medical conditions where other treatments have had limited success, and as a complementary treatment alongside conventional pharmaceuticals.
How Can Medical Cannabis Help with Epilepsy?
Before proceeding further, it is crucial to emphasise that medical cannabis should never be viewed or advertised as a cure-all for epilepsy. Instead, it should be seen as a potential supplementary treatment that may help reduce seizure activity and improve the overall quality of life for those with epilepsy and other chronic conditions.
When incorporated into a tailored and managed treatment plan, medical cannabis has been shown to enhance overall control of epileptic seizures. Indeed, it is the only non-pharmaceutical treatment option approved by the National Institute for Health and Care Excellence (NICE) in England for two rare forms of epilepsy.
The Anti-Seizure Effect of Medical Cannabis
Studies have demonstrated that the cannabinoids in CBMPs can reduce seizure activity. A 2018 retrospective study on the safety and efficacy of CBD involving 607 patients aged 1 to 62 years found that high-CBD medical cannabis products reduced the frequency and severity of seizures across various epilepsy types.
This is supported by a 2019 study titled “Use of Cannabidiol in the Treatment of Epilepsy: Efficacy and Security in Clinical Trials”. The key findings were:
“CBD is a non-psychotropic cannabinoid extracted from Cannabis sativa, which has received scientific interest due to its medical applications. It has shown efficacy as an anti-seizure, antipsychotic, neuroprotective, antidepressant, and anxiolytic compound. The neuroprotective activity of CBD is believed to be linked to its anti-inflammatory and antioxidant properties.”
Thus, CBD appears to be an effective anti-seizure treatment when administered in the correct dose and delivery system.
What About THC?
While CBD has a better anticonvulsant profile in most clinical trials and is largely devoid of psychoactive effects and abuse potential, THC may also offer some anti-seizure benefits, though research on its effectiveness is less conclusive.
Despite this, THC is not devoid of medicinal and therapeutic benefits for epilepsy sufferers. To fully understand how THC may benefit those with epilepsy, we need to discuss the “entourage effect”. This widely accepted theory posits that “the active cannabis components work together to amplify therapeutic effects while reducing the psychoactive side effects of THC.”
When cannabinoid compounds are administered in their natural form, they contain hundreds of different molecules that interact synergistically, increasing their effectiveness compared to isolated cannabinoids such as CBD or THC extracted from hemp or cannabis plants.
Therefore, adding small levels of THC to a CBD-rich product may potentially enhance the anti-seizure effect. THC has also been shown to offer neuroprotective benefits, reduce inflammation and pain, improve sleep quality, and exhibit antidepressant and antianxiety properties.
CBD also shows promise in reducing inflammation and pain, providing relief from symptoms associated with epilepsy and other chronic conditions. Its anxiolytic effects have been beneficial for those suffering from anxiety disorders, which can often accompany epileptic seizures.
A recent study published in the British Journal of Pharmacology found that secondary cannabinoids may reduce seizures. Cannadivarinic acid (CBDVA), cannabidivarin (CBDV), cannabigerovarinic acid (CBGVA), and cannabigerolic acid (CBGa) were linked to antiepileptic effects.
This indicates that while we already understand how cannabis may benefit epilepsy treatment, there is still much to learn about the potential benefits of other cannabinoid compounds in medical cannabis products. With the current wave of cannabis legalisation, the opportunities for researchers have never been greater, and we can hope for further discoveries soon.
Are There Any Side Effects of Medical Cannabis?
Yes, like all medications, medical cannabis has potential side effects. The most common side effects reported include drowsiness, dizziness, and fatigue. Some individuals may also experience short-term memory loss, confusion, and, in rare cases, psychotic episodes. However, these adverse events are typically mild and well-tolerated.
How to Obtain Medical Cannabis for Epilepsy in the UK
Although there has been a surge in ‘over-the-counter’ CBD products in recent years, the majority of these options are not medical products. The medicinal cannabis sector is subject to far stricter regulations, and any product claiming to be ‘medicinal’ must fulfil various requirements before a doctor can prescribe it.
If you are interested in incorporating medicinal cannabis products into your treatment plan, it is crucial to seek guidance from a registered, qualified, and experienced doctor. They can provide the correct CBMP for your specific epileptic symptoms and advise on dosage frequency and size.
If you have been diagnosed with one of the two rare types of epilepsy, Dravet Syndrome or Lennox-Gastaut Syndrome, and are over the age of 12, you may be eligible for an NHS-funded CBMP prescription. Otherwise, you will need to go through a private clinic.
