An Australian study of illicit medicinal cannabis used to treat childhood epilepsy found parents overwhelmingly considered the extracts as effective, although most samples contained low doses of cannabidiol, contrary to parents’ expectations.
The pioneering study found Australian parents who turned to illicit medicinal cannabis to treat children with epilepsy overwhelmingly considered the extracts as “effective”. Contrary to parental expectations, extracts generally contained low doses of cannabidiol (CBD) – a commonly considered to be a key therapeutic element and that has been successfully used in recent clinical trials to treat epilepsy.
The research, which commenced two years ago by the University of Sydney’s Lambert Initiative for Cannabinoid Therapeutics, not only sheds light on the composition of cannabis used in the community but also reveals the legal, bureaucratic, and cost issues faced by families who relied on the products, as well as demonstrating the barriers to accessing medicinal cannabis.
The study found that the main psychoactive ingredient in cannabis, tetrahydrocannabidiol (THC), and the closely related compound THCA, were present in most extracts, although the quantity was generally not enough to produce intoxicating effects. Just over half the extracts were associated with a seizure reduction of 75%-100%, which reinforces observations from animal studies and case reports of anti-convulsant effects of THC and THCA. As well, 65% were associated with other beneficial effects like improved cognition (35%) and language skills (24%).
Lead author and PhD candidate with the Lambert Initiative at the Brain and Mind Centre, Anastasia Suraev, said just under half the families who used medicinal cannabis reduced their antiepileptic medication. “Our findings highlight the huge unmet clinical need in the management of treatment-resistant epilepsy in childhood,” said Suraev, from the School of Psychology.
Corresponding author and academic director of the Lambert Initiative, Professor Iain McGregor, said: “Although the illicit extracts we analysed contained low doses of CBD, three in four were reported as ‘effective’, indicating the importance of researching the cannabis plant in its entirety for the treatment of epilepsy.
“And despite the overwhelming presence of generally low levels of THC, concentrations did not differ between samples perceived as ‘effective’ and ‘ineffective’.
“Our research indicates there is a potential role for other cannabinoids, alone or in combination with conventional drugs, in treatment-resistant epilepsy – and this warrants further investigation so we can hopefully develop safer and more effective medicines.”
Recent surveys suggest that many parents are using illicit cannabis extracts in the hope of managing seizures in their children with epilepsy. In the current Australian study we conducted semi-structured interviews with families of children with diverse forms of epilepsy to explore their attitudes towards and experiences with using cannabis extracts. This included current or previous users of cannabis extracts to treat their child’s seizures (n = 41 families), and families who had never used (n = 24 families). For those using cannabis, extracts were analysed for cannabinoid content, with specific comparison of samples rated by families as “effective” versus those rated “ineffective”. Results showed that children given cannabis extracts tended to have more severe epilepsy historically and had trialled more anticonvulsants than those who had never received cannabis extracts. There was high variability in the cannabinoid content and profile of cannabis extracts rated as “effective”, with no clear differences between extracts perceived as “effective” and “ineffective”. Contrary to family’s expectations, most samples contained low concentrations of cannabidiol, while Δ9-tetrahydrocannabinol was present in nearly every sample. These findings highlight profound variation in the illicit cannabis extracts being currently used in Australia and warrant further investigations into the therapeutic value of cannabinoids in epilepsy.
A Suraev, N Lintzeris, J Stuart, RC Kevin, R Blackburn, E Richards, JC Arnold, C Ireland, L Todd, DJ Allsop, IS McGregor