Author link Abhimanyu S.Ahuja
Source Science Direct
Volume 8, Issue 3, September 2019, Pages 200-201
According to the Mayo Clinic “Epilepsy is a central nervous system (neurological) disorder in which brain activity becomes abnormal, causing seizures or periods of unusual behavior, sensations, and sometimes loss of awareness,” and epilepsy can affect anyone male or female no matter what race or age they are.1 The symptoms are not always the same and depend on the type of seizure, however, for each individual person symptoms tend to be similar from one episode to the next.1 According to UChicago Medicine epileptic seizures are unprovoked “provoked seizures result from some immediately recognizable stimulus (for example, low blood sugar in people with diabetes), while unprovoked seizures have no immediately recognizable cause.”2 Epilepsy for certain patients can debilitating as they can have hundreds of seizures a day, and thus treatment for such patients is essential.
Epilepsy treatment options can include medication, diet therapy, and surgery. Traditionally used antiepileptic drugs (AEDs) tend to support inhibitory processes or inhibit excitatory processes.3 AEDs can cause adverse effects including cognitive impairments, idiosyncratic effects such as skin rashes, and chronic effects such as weight gain.4 Unfortunately, many of those with debilitating epilepsy do not respond to antiseizure drugs: “Approximately 1 million people in the United States continue to have seizures despite adequate treatment with antiseizure drugs, representing 40% of those with epilepsy, and 80% of the cost of epilepsy.”5
Drug-resistant epilepsy (DRE) is a serious concern and in additional to surgical interventions cannabis-based treatments are being viewed as potential remedy.
Much of the initial reports for cannabis use in seizure control centered on the compound 9-Δ-tetrahydrocannabinol (THC). However, due to the psychoactive properties of THC potential utility was somewhat limited and recent research has focused on non-psychoactive compounds such as cannabidiol (CBD).6 The anti-seizure effects of CBD may come from mechanisms such as functional agonism or antagonism at several 7-transmembrane receptors, ion channels, and neurotransmitter transporters.6 Recently, another compound that also is without psychoactive effects known as CBDV has also shown anti-seizure properties both in vivo and in vitro.6
Many reports exist on illicit cannabis use through the smoking of marijuana by patients as a self-treatment. For example, a 1975 paper describes a 24-year old patient with drug-resistant seizures that became seizure free after beginning to smoke marijuana.6 However, such uncontrolled treatment presents health risk based on smoke inhalation and a lack of control of dosage. Therefore, more recent work on cannabis for epileptic patients has focused on oral preparations as they can provide safer and far more controlled doses.6 Additionally, many of those who seek cannabis-based treatments for their epileptic seizures would like to avoid the psychoactive feelings brought upon by THC.
Interpretation of the data on cannabis use for the treatment of epilepsy has been quite difficult thus far due to the uncontrolled nature of these observations.6 For example, significant interest was sparked from the case of, a young girl named Charlotte with SCN1A-confirmed Dravet syndrome, who showed a great reduction in her seizures after using a CBD enriched extract.6 However, recently four randomized controlled trials (RCTs) have been completed of pharmaceutical grade CBD.7 One RCT completed on the use of the CBD drug Epidiolex® for the treatment of Dravet Syndrome showed a significant decrease in convulsive seizures per month from 12.9 to 5.9 with CBD treatment versus 14.9 to 14.1 with placebo.7 However, in the case of non-convulsive seizures no significant improvement was shown.7 One RCT completed on the use of the CBD drug Epidiolex® for the treatment of Lennox–Gastaut syndromes showed that after 14 weeks of treatment median percentage reduction in drop seizure frequency per month from baseline was 43.9% in the CBD group and 21.8% in the placebo group (p = 0.0135).7 Beyond Epidiolex® an open-label study has been conducted on the drug Tilray.8 Tilray 2:100 is a mixed compound that contains 2 mg/mL THC and 100 mg/mL CBD.8 The study noted a reduction in motor seizures of 71%, with a 50% responder rate of 63%.8 These formalized studies show strong evidence of cannabis-based treatments being viable options in the treatment of certain forms of epilepsy. However, there are some potential side effects to be noted with the use of these medications. For example, side effects of Epidiolex® include sleepiness, decreased appetite, diarrhea, increase in liver enzymes, rash, sleep problems, and infections.9
Cannabis and cannabis-based treatments offer promising alternatives to traditional AEDs. Due to the unfortunate fact that many patients suffer from DRE, cannabis-based treatments have great value. Cannabis-based treatments offer some patients with DRE a great remedy for their condition with limited side effects. This option may prevent some patients with DRE from needing to consider more invasive options such as surgical interventions. In case studies, open label studies, and RCTs, one can see drastic improvements in the frequency of seizures in patients with certain forms of epilepsy. It is imperative to continue research into cannabis as a potential primary treatment for epilepsy, particularly those with DRE, to help improve quality of life for millions of people suffering from epilepsy.