A series of articles published in the journal Epilepsia investigate the use of medical marijuana and pure cannabidiol in treating severe forms of epilepsy.
Last month, the American Academy of Neurology produced a review of all available evidence on the use of marijuana to treat brain diseases. However, their conclusion was that there is only limited evidence to support the use of medical marijuana beyond treating multiple sclerosis symptoms.
This conclusion is challenged in the new Epilepsia articles. The first of these describes a case study of a mother who provides medical marijuana to her child with Dravet syndrome - a severe form of epilepsy. The child's frequency of seizures reportedly decreased from 50 convulsions per day to 2-3 convulsions each month as a result of this adjunct therapy.
The form of marijuana administered to the child is known as "Charlotte's Web" - a strain of marijuana high in cannabidiol (CBD) and low in tetrahydrocannabinol (THC), which is the primary psychoactive ingredient in marijuana.
The family is based in Denver, CO - one of the states that recently legalized marijuana.
"Colorado is 'ground zero' of the medical marijuana debate," claims article author Dr. Edward Maa, chief of the Comprehensive Epilepsy Program at Denver Health. "As medical professionals it is important that we further the evidence of whether CBD in cannabis is an effective antiepileptic therapy."
Another article in the series reviews the current evidence on CBD use to treat neurological disorders such as anxiety, schizophrenia and addiction, as well as epilepsy. The article notes that some studies have found that CBD and THC have anticonvulsive properties. However, these studies were only in animal models, and there was not much data for chronic recurrent seizures.
Other recent studies have found that medical marijuana rich in CBD and THC are effective in seizure control, but they rely on anecdotal data.
Dr. Orrin Devinsky, director of the Comprehensive Epilepsy Center at NYU Langone Medical Center in New York and Saint Barnabas Institute of Neurology and Neurosurgery in New Jersey, explains:
Studies have found that medical marijuana rich in CBD and THC are effective in seizure control, but they rely on anecdotal data.
"While cannabis has been used to treat epilepsy for centuries, data from double-blind randomized, controlled trials of CBD or THC in epilepsy is lacking. Randomized controlled studies of CBD in targeted epilepsy groups, such as patients with Dravet or Lennox-Gastaut syndromes, are in the planning stages."
"There is a critical need for new therapies," agrees Dr. Maria Roberta Cilio, director of research in Pediatric Epilepsy of the Comprehensive Epilepsy Center at UCSF Benioff Children's Hospital in San Francisco. "Especially for childhood-onset treatment-resistant epilepsies that impair quality of life and contribute to learning and behavioral disorders."
"Rigorous investigation of the safety and efficacy of medical marijuana or individual components such as CBD are necessary for patients with epilepsy before any conclusion is made," she adds.
The editors-in-chief of Epilepsia - Drs. Gary Mathern and Astrid Nehlig - comment on the series:
"There is much interest in the therapeutic potential of medical marijuana and CBD in treating epilepsy. We would like your perspective on this important issue and ask that patients, clinicians, and medical professionals visit [this website] to provide feedback on the use of medical marijuana in epilepsy."
Recently, Medical News Today also reported on the publication by Epilepsia of a new clinical definition of epilepsy. This definition, provided by a task force of epilepsy experts, now permits the possibility of epilepsy becoming "resolved" in certain scenarios.
However, the experts behind the definition were careful to explain that the new status of "resolved" epilepsy is not the same as "remission" or "cure."