According to The Epilepsy Foundation of America, 1 in 26 people will develop epilepsy in their lifetime.
In this article, CannaMD details how the active chemical compounds in medical marijuana contribute to epilepsy relief, helping to stop seizures.
What is a Seizure?
A seizure is an abnormal, uncontrolled electrical disturbance in the brain. There are three main types of seizures:
- Generalized onset
- Focal onset
- Unknown
Generalized onset seizures affect both sides of the brain or groups of cells on both sides of the brain at the same time and include common seizure types such as tonic-clonic, absence, and atonic.
Focal onset seizures begin on one side of the brain or in a group of cells on one side of the brain. There are two types of focal onset seizures: aware and impaired-awareness seizures.
When the onset of a seizure is not known and the seizure is not witnessed, it is classified as an unknown onset seizure.
To learn more about the different types of seizures and how they affect the brain and body, see: The Epilepsy Foundation of America.
What is Epilepsy?
Epilepsy is a diverse group of neurological disorders characterized by a tendency to cause seizures that begin in the brain. Epilepsy is typically diagnosed if a person has two unprovoked seizures (or one unprovoked seizure with the likelihood of more) that were not caused by some known and reversible medical condition like alcohol withdrawal or extremely low blood sugar.
Over 65 million people worldwide are currently diagnosed with epilepsy. At least one million Americans suffer from refractory epilepsy, which has no known cure and does not respond to medication.
Fortunately, Florida state law allows for the treatment of epilepsy with medical marijuana – an increasingly popular medication alternative that has demonstrated clinically significant benefits for countless epilepsy patients.
Medical Marijuana and Seizure Studies
On June 25, 2018, the U.S. Food and Drug Administration (FDA) approved the first drug comprised of an active ingredient derived from marijuana for the treatment of seizures: Epidiolex. This medication focuses specifically on two rare and severe forms of epilepsy, Lennox-Gastaut syndrome and Dravet syndrome, in patients two years of age and older. It is also the first FDA-approved drug for the treatment of patients with Dravet syndrome.
Before receiving its FDA approval, Epidiolex had to undergo a number of clinical trials. Below, we’ve outlined some of the findings from these trials and other studies focused on marijuana and seizures:
STUDY: Effect of Cannabidiol on Drop Seizures in the Lennox–Gastaut Syndrome
JOURNAL: The New England Journal of Medicine
FINDING: Using CBD in combination with traditional seizure medication decreased the frequency of atonic seizures.
DETAILS: Atonic seizures are a form of generalized onset seizures that result in complete muscle laxity. These seizures are also called drop seizures because people who have them will fall over if standing when they happen. Drop seizures are common among people with Lennox-Gastaut and Dravet syndromes.
In a double-blind, placebo-controlled trial conducted at 30 clinical centers, 225 patients with Lennox–Gastaut syndrome who experienced two or more drop seizures per week during a 28-day baseline period were selected to receive an oral solution made from marijuana cannabinoid, cannabidiol (CBD).
Patients were randomly selected to receive a CBD dose of either 20mg per kilogram of body weight, 10mg per kilogram, or matching placebo.
The results of the study found that patients taking CBD experienced a “significant” decrease in the rate of atonic seizures over the placebo group. The decrease in atonic seizures for each group were as follows:
- 41.9% decrease (20mg CBD group)
- 37.2% decrease (10mg CBD group)
- 17.2% decrease (placebo group)
STUDY: Trial of Cannabidiol for Drug-Resistant Seizures in the Dravet Syndrome
JOURNAL: The New England Journal of Medicine
FINDING: CBD decreased the number of convulsive seizures experienced by those suffering from Dravet syndrome.
DETAILS: Dravet syndrome is a rare genetic epileptic encephalopathy (dysfunction of the brain) that is very resistant to traditional medication and has a high mortality rate. In a double-blind, placebo-controlled trial, 120 children and young adults with Dravet syndrome and drug-resistant seizures were randomly selected to receive either CBD oral solution at a dose of 20mg per kilogram of body weight per day or a placebo (in addition to standard anti-epileptic treatment).
The results of the study concluded:
- 43% of CBD patients experienced a reduction of at least 50% in convulsive seizure frequency
- Only 27% of placebo patients experienced a reduction of at least 50% in convulsive seizure frequency
- The frequency of total seizures of all types was significantly reduced by CBD (however, there was no significant reduction in non-convulsive seizures)
- The percentage of people who became seizure-free was 5% with CBD and 0% with placebo
STUDY: Cannabidivarin Is Anticonvulsant in Mouse and Rat
JOURNAL: British Journal of Pharmacology
FINDING: CBVD may be an effective anticonvulsant for a broad range of seizure models.
DETAILS: A 2012 mouse and rat study researching the effects of marijuana cannabinoid, cannabidivarin (CBVD) showed that CBVD showed strong potential as an anticonvulsant.
Study authors wrote:
Our most important finding is that CBDV possesses strong anticonvulsant properties in a range of in vivo seizure models that parallel a variety of human seizure types and pathologies; anticonvulsant effects were also seen after oral, as well as i.p., administration.
Researchers also noted that:
[T]he significant anticonvulsant effects and favorable motor side effect profile demonstrated in this study identify CBDV as a potential standalone AED or as a clinically useful adjunctive treatment alongside other AEDs.
STUDY: Cannabidiol Displays Antiepileptiform and Antiseizure Properties In Vitro and In Vivo
JOURNAL: The Journal of Pharmacology and Experimental Therapeutics
FINDING: CBD produced reductions in median seizure severity, tonic-clonic seizures, and mortality.
DETAILS: In a 2010 animal study, researchers found:
CBD had beneficial effects on seizure severity and lethality in response to PTZ administration without delaying the time taken for seizures to develop. CBD (100 mg/kg) demonstrated clear anticonvulsant effects in terms of significant reductions in median seizure severity, tonic-clonic seizures, and mortality.
Particularly striking effects were that < 10% of animals developed tonic-clonic seizures or died when treated with CBD in comparison to approximately 50% of vehicle-treated animals.
The present data strongly substantiate a number of earlier in vivo studies suggesting that CBD has anticonvulsant potential.
The scientists involved in the study concluded:
In the future, it will be of interest to extend studies to other animal seizure models and also to combination therapies with selective AEDs to determine the full clinical anticonvulsant potential of CBD against a range of epilepsy phenotypes.