Kelli Whitlock Burton

December 29, 2021 – Whole-plant cannabis is linked to a significant reduction in seizures in children with severe treatment-resistant epilepsy, early research suggests.

In a small study, children with severe treatment-resistant epilepsy treated with a range of whole-plant extract cannabis-based medical products (CBMPs) reported an 86% reduction in monthly seizures.

All participants had no improvement with traditional antiepileptic drugs (AEDs).

The study adds to a small but growing body of research investigating whole-plant cannabis medicines containing tetrahydrocannabinol (THC) in pediatric epilepsies.

"Although we have previously noted the superior efficacy of whole-plant medical cannabis is a previous group of children, to find that the effect of the treatment resulted in an 86% average reduction in seizures is remarkable and testament to the clear clinical value of this intervention," lead author Rayyan Raja Zafar, a doctoral student with the Centre for Psychedelic Research and Neuropsychopharmacology, Imperial College London, U.K., said.

The study included 10 children under age 18 years who were recruited through MedCann Support and End Our Pain, charities that represent children who use medical cannabis to treat intractable epilepsies. Data were collected from patients' parents or caregivers between January and May 2021.

Patients had a range of epilepsy causes. Two patients experienced no symptom improvement after taking Epidyolex, a purified cannabidiol (CBD) approved by the European Commission in 2019 for the treatment of rare forms of epilepsy. The formulation was approved by the US Food and Drug Administration in 2018 under the name Epidiolex.

All patients reported fewer seizures, ranging from a decrease in monthly seizure activity of 62.5% to 100%. The average decrease was 86%.

"It appears that whole-plant cannabis is superior to CBD alone, and the reasons for this are speculative," Zafar said.

"It is known that THC does have independent antiseizure activity,” Zafar added.

Tyler Allison, MD, associate professor of pediatrics at Children's Mercy Kansas City, MO, noted that researchers chose patients based on their long-standing use of whole-plant medical cannabis oils, introducing a selection bias.

"The response is still interesting, and I think it needs to be studied further with better parameters in place to reduce bias, but I don't think it's fair to evaluate the amount of decrease in seizure frequency when the population studied was only patients who responded to the treatment," said Allison, who was not involved with the research.