Marijuana for the treatment of epilepsy

Marijuana has been used for the treatment of medical conditions for over 4000 years. The medical use of marijuana is currently a hotly debated topic. There are some anecdotal reports of patients using marijuana to treat seizures. The popular media has recently run stories about patients using marijuana for their epilepsy. Some patients describe that marijuana improves their seizure control, while others indicate that marijuana exacerbates seizures. Given all the attention about marijuana and epilepsy, it is not surprising that patients are, with increasing frequency, asking the Minnesota Epilepsy Group’s opinion about treating seizures with marijuana.

The purpose of this article is to highlight a recent study which reviews the literature in tremendous detail in order to answer the following questions:

1) Does marijuana improve seizure control?
2) Is marijuana safe?


STUDY DESIGN
The authors did a very extensive review of the literature- in order to identify all papers that performed randomized control trials assessing marijuana in the treatment of epilepsy.

RESULTS
The study found: ” four randomized reports which included a total of 48 patients, each of which used cannabidiol as the treatment agent. (Cannabidiol is an important extract of marijuana). One report was an abstract, and another was a letter to the editor. Anti-epileptic drugs were continued in all. Details of randomisation were not included in any study. There was no investigation of whether control and treatment groups were the same or different. All the reports were low quality. “

As far as seizure control, little information is provided: One study reported two of four treated patients becoming seizure free for 3 months. The other studies either reported no benefit, or the effect was not clearly stated.

CONCLUSIONS
“No reliable conclusions can be drawn at present regarding the efficacy of cannabinoids as a treatment for epilepsy. The dose of 200 to 300 mg daily of cannabidiol was safely administered to small numbers of patients, for generally short periods of time, and so the safety of long term cannabidiol treatment cannot be reliably assessed.”

Thus, at this time, there is a lack of scientific evidence to recommend marijuana for the treatment of epilepsy. To quote the American Epilepsy Society:

“The lack of information does not mean that marijuana is ineffective for epilepsy. It merely means that we do not know if marijuana is a safe and efficacious treatment for epilepsy. Healthcare professionals, patients, and caregivers are reminded that use of marijuana for epilepsy may not be advisable due to lack of information on safety and efficacy, and that, despite some states legalizing the use of medical marijuana, it is against Federal Law to possess or use marijuana. In addition, little is known about the long term effects of using marijuana in infants and children, and chronic exposure during adolescence has been shown to have lasting negative effects on cognition and mood. Such safety concerns coupled with a lack of evidence of efficacy in controlled studies result in a risk/benefit ratio that does not support use of marijuana for treatment of seizures at this time. The American Epilepsy Society is supportive of well-designed research to determine the safety and efficacy of marijuana in the treatment of epilepsy.”