Recent studies published within six months of each other make two diametrically opposed claims: One points to cannabis as the likely cause of seizures while the other states that cannabis may prevent them. But the connection between marijuana and seizures is a complex one. And while these studies are grabbing headlines for their contradictory statements, it’s important to remember that they arise from highly limited studies that don’t involve the kinds of “natural” cannabis products typically used for medicinal purposes.
Marijuana & Seizures: A Complicated Relationship
The question of whether—and how—cannabis can affect seizure activity in the brain has been raised numerous times. Anecdotal evidence from a number of medical cannabis consumers says that it can in both ways.
People with seizure disorders, and parents of children who have them, claim that cannabis, particularly cannabidiol (CBD), reduces the frequency and severity of seizures. Now, a study carried out in the spring of 2017 by researchers at the New York University Langone Medical Center appears to confirm CBD’s beneficial effects, to an extent.
On the other hand, some people say that their seizures resulted from smoking or eating cannabis, and some mainstream medical publications list seizures as a risk of cannabis use. In September 2017, another study conducted at Japan’s University of Tsukuba appeared to confirm that as well, with research that showed high doses of tetrahydrocannabinol (THC) and “spice,” a synthetic form of marijuana, could actually trigger seizures.
Who’s right? The answer is skewed by the limitations of these studies, both of which are based on artificial conditions and highly specific forms of cannabis that most medical consumers don’t typically encounter.
CBD Oil May Help Treatment-Resistant Seizures
The New York University study, and a few other studies, were prompted by comments from parents of children with severe forms of epilepsy such as Dravet Syndrome, which causes almost constant seizure activity and is often resistant to standard medications. These parents said that cannabis was able to reduce a child’s seizure activity when no other medications could.
To test these claims, researchers compared an FDA-approved cannabis-based medication called Epidiolex—a 99% pure CBD oil concentrate—to both a placebo and a standard epilepsy medication called Onfi. Compared to the placebo, 54% of patients taking Epidiolex had fewer seizures—and in 2%, seizures stopped altogether. Compared to Onfi though, the study found minimal differences in effectiveness. Based on these results, epilepsy specialists have cautiously allowed that Epidiolex could be used for “compassionate care” when other medications fail to work.
But that study looked only at a single, FDA-approved medication based on CBD—and the study was funded by its manufacturer, GW Pharmaceuticals. Still, this study does suggest that CBD plays a role in suppressing seizures and adds more evidence to the growing list of health benefits provided by this non-psychoactive cannabis compound.
Could THC & “Spice” Trigger Seizures?
In stark contrast, researchers in the Tsukuba study claim that cannabis can cause seizures—but only certain strains, in high doses and in mice. The study worked only with very high concentrations of natural THC, the psychoactive ingredient responsible for marijuana’s “high,” and found that in these controlled circumstances THC could in fact trigger seizures.
The same study examined the seizure-causing effects of one form of synthetic marijuana, known as “spice”. Spice was developed in the early 2000s as a way to get the marijuana high without the traces of THC that could show on a drug test. Since then, more than 150 different variants of spice have been lab-created, all of them far more potent than natural cannabis.
Like the natural cannabis compounds CBD and THC, spice in all its forms binds to the body’s natural endocannabinoid receptors. But although spice stimulates those receptors in ways similar to THC, it doesn’t behave in the body the same way that natural cannabis does, and that can cause very different effects.
What’s more, spice usually contains other substances that also break down and create byproducts that most likely cause actions of their own on the endocannabinoid receptors. The Japanese study focused on just one variant of spice, called JWH-018, administering it in very high doses, and found that this drug can also trigger seizures.
Spice can’t replicate the health benefits of natural cannabis and is sought after mostly by recreational users for its potency and ability to cheat a drug test. And although they sound a warning about the danger of seizures caused by cannabis, the Tsukuba research team acknowledge that those results come from administering concentrated forms of THC and JWH-018 at doses far higher than the typical consumer of recreational or medicinal cannabis would ever seek out. CBD was not included in this study at all.
The Cannabis-Seizure Connection Needs More Study
It’s clear there’s a connection between cannabis and seizures, but it isn’t entirely clear what that connection is.
For now, though, research indicates—and personal experiences validate—that CBD can calm seizure activity. And mainstream healthcare professionals point out that the risk of having a seizure from using cannabis is largely confined to a few specific groups: people who already have a seizure disorder, or who take anti-seizure medications or antipsychotic drugs that have their own risk of causing seizures.
More comprehensive research could unravel the complicated relationship between cannabis and seizures, but federal regulations on marijuana keep it on the DEA’s Schedule 1 of highly addictive and dangerous drugs. That makes it difficult to conduct the rigorous research that clears the air and helps cannabis consumers find the answers they’re looking for.
If you’re new to cannabis and want to learn more, take a look at our Cannabis 101 post. HelloMD can help you get your medical marijuana recommendation; it’s easy, private and 100% online.
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Recent studies published within six months of each other make two diametrically opposed claims: One points to cannabis as the likely cause of seizures while the other states that cannabis may prevent them. But the connection between marijuana and seizures is a complex one. And while these studies are grabbing headlines…
Marijuana and ‘spice’ could trigger seizures, study says
While a number of studies have suggested that marijuana may be effective for reducing seizures, new research cautions that potent and synthetic forms of the drug have the opposite effect.
Share on Pinterest Researchers suggest that the use of potent cannabinoids have the potential to trigger seizures.
Researchers from the University of Tsukuba in Japan found that natural tetrahydrocannabinol (THC) – the psychoactive chemical in marijuana – and the synthetic cannabinoid JWH-018 caused seizures in mice.
Study leader Olga Malyshevskaya and colleagues say that their findings – which are published in the journal Scientific Reports – should serve as a “public alert” to the potential harms caused by high-potency and synthetic marijuana.
While marijuana remains that “most commonly used illicit drug” in the United States, it is becoming increasingly legalized in individual states for medicinal purposes, recreational purposes, or both.
There has been increasing research for the use of marijuana – particularly a cannabinoid in the drug called cannabidiol (CBD) – in the treatment of seizures in patients with epilepsy, though a debate surrounding its efficacy continues.
The new study from Malyshevskaya and team suggests that general use of high-potency marijuana – that is, marijuana that contains high amounts of THC – may actually trigger seizures.
The research also found that seizures could be prompted by JWH-018, which is a manmade cannabinoid that is the primary component of the synthetic marijuana known as “spice.”
The researchers came to their findings by analyzing the brain activity of male mice after they received THC or JWH-018.
THC was given to the rodents in doses of 10 milligrams per kilogram (the equivalent to around 0.8 milligrams per kilogram in humans) and JWH-018 was administered in doses of 2.5 milligrams per kilogram (the equivalent to around 0.2 milligrams per kilograms in humans).
The team implanted electroencephalography (EEG) and electromyogram electrodes into the brains of the mice, which allowed them to monitor any seizure-related electrical activity in response to the drug compounds.
The movement and behavior of the rodents was also monitored through video recording.
The study revealed that the mice experienced seizures shortly after administration with both THC and JWH-018, though seizure frequency was significantly higher with JWH-018.
Seizure-related brain activity persisted for 4 hours after the administration of each drug, the team reports, but brain activity had returned to normal by the next day.
Interestingly, the researchers found that pre-treating the mice with AM-251 – which is a compound that binds to the cannabinoid-1-receptor – prevented seizures in response to THC and JWH-018.
As such, the team suggests that cannabinoid receptor antagonists could be useful for preventing seizures in the case of marijuana overdose.
According to the researchers, their results “provide strong evidence” that both plant-derived and synthetic cannabinoids have the potential to trigger seizures.
“On the other hand,” the authors note, “a substantial body of literature on cannabinoids in animal models shows mostly anticonvulsive effects.”
“However,” they add, “few of these used EEG recordings to assess epileptic events and many of them induced seizures either electrically or pharmacologically, changing signaling pathways and brain states prior to cannabinoid application.”
The team cautions that the doses of THC and JWH-018 used in their study were high and may not represent the doses normally seen with medicinal or recreational use in humans.
“It would be interesting in the future to also test lower doses, typically used medicinally or recreationally to determine whether the effect is lost or diminished,” they add.
Still, they believe that their findings should be viewed as a warning of the potential dangers of cannabinoids, particularly synthetic marijuana.
“ Our study is quite important because unaware of the particularly severe effect by those cannabinoids, people see marijuana as a soft drug, without dangerous health effects.”
High-potency natural and synthetic cannabinoids were found to trigger seizures in mice, say researchers, with the latter posing the strongest effects.