Why Cannabis May Be Useful in Treating Epilepsy

Cannabis and, in particular, cannabidiol (CBD), have sparked growing interest for their use in the treatment of epilepsy, especially in refractory cases in which conventional therapies fail. This exploration is based on various studies and scientific advances that have highlighted cannabinoids’ potential in relieving this neurological disease.

Epilepsy is one of the most common neurological conditions worldwide, and a significant percentage of patients do not respond adequately to conventional treatments. In this context, cannabinoids, and specifically CBD, have emerged as a complementary therapeutic option. In fact, in the treatment of epilepsy, two cannabinoid-based drugs have garnered a lot of attention, for years: Epidiolex and Sativex.

Epidiolex is a cannabidiol-based oral solution that has been approved by the U.S. Food and Drug Administration (FDA) to treat specific types of severe and uncommon epilepsy, such as Dravet syndrome and Lennox-Gastaut syndrome. Sativex is an oral spray containing a 1:1 combination of CBD and tetrahydrocannabinol (THC). Although its main use has been to reduce severe pain, especially in cases of multiple sclerosis, research has also been carried out on its potential in the treatment of other pathologies, including epilepsy.

How might cannabis treat epileptic seizures?

An epileptic seizure triggers the creation and release of a natural chemical in our brain called 2-arachidonoylglycerol (2-AG), a compound that is rapidly released at the onset of the seizure and acts to mitigate its intensity. This is valuable because it is an endocannabinoid that mimics THC, just like anandamide. Endocannabinoids, in general, appear to inhibit excessive excitation in the brain, and are released when excitatory neurons exceed a threshold.

However, the rapidity with which 2-AG breaks down after use in the brain causes more confusion and amnesia after the seizure. This is because it is converted to arachidonic acid, which can lead to inflammation and the constriction of blood vessels in the brain. It is theorized that a drug that impedes the conversion of 2-AG into arachidonic acid will not only avert the harmful constriction of blood vessels, but also increase the concentration of 2-AG.

One theory is that by introducing THC and/or CBD into the brain it could function like 2-AG, but without its rapid disintegration, helping to control seizures in the long term and minimizing disorientation after a seizure. Another theory is that CBD blocks signals transmitted by lysophosphatidylinositol (LPI), another endogenous endocannabinoid that can be sequestered and used to induce seizures. This also indicates that CBD could be used as a preventative drug.

What does current research tell us about this?

According to various studies, patients treated with CBD, either alone or in combination with other antiepileptic drugs, have exhibited not only a reduction in the frequency of seizures, but also improvements in other aspects, such as emotional, cognitive and motor well-being, as well as socialization.

It is critical, however, to recognize that not all cases of epilepsy respond to CBD treatment. In some cases it may be necessary to add THC, although this should be done with caution, since, as a biphasic compound, it can relieve or, conversely, trigger seizures, depending on the dose.

Although the use of cannabis and its derivatives, particularly CBD, in the treatment of epilepsy shows promising results, a more thorough understanding of their action mechanisms is still required, as well as a careful evaluation of drug interactions and side effects. Therefore, continued research in this area is crucial to establish its efficacy and safety with greater certainty.