Epilepsy Seizures Reduced With Marijuana Extract, New Study Shows

A medicine derived from marijuana may provide relief to people suffering from severe epilepsy who could not be helped by other treatments, a new study recently conducted by the New York University in New York City showed.

The study involved 137 people, ranging in age from toddlers to adults, who all had experienced seizures due to severe epilepsy, LiveScience.com reported on Monday.

The participants took an extract made from cannabis plants daily for 12 weeks. During that time, the number of seizures they experienced fell by an average of 54 percent.

The participants knew they were receiving the extract, the researchers said. However, the study did not have a comparison group of people with the same condition who would have received a placebo or no marijuana drug at all.

"While the findings are promising, more research is needed, such as randomized-controlled trials to help eliminate the possibility of a placebo effect," said study author Dr. Orrin Devinsky, director of New York University Langone Comprehensive Epilepsy Center. The study was funded by U.K.-based firm GW Pharmaceuticals that focuses on developing cannabinoid prescription medicines.

The main ingredient in the drug the participants took was cannabidiol, which does not have psychoactive properties. It is the THC compound in marijuana that causes the "high" feeling.

Originally, there were 213 participants but some dropped out of the research before the 12-week mark was reached. This includes six percent of people who stopped taking the marijuana drug because of its side effects, which more than 10 percent of the participants experienced. Twenty-one percent experienced sleepiness, 17 percent had diarrhea and fatigue, while 16 percent said their appetites decreased.

The study's participants previously underwent treatments for their epilepsy, like anti-epileptic drugs, diet changes, surgery and neurostimulation therapies, according to Devinsky, who told LiveScience.com that "about one-third of patients with epilepsy do not respond to medications."

Previous findings related to the marijuana extract, presented at the American Epilepsy Society meeting in October 2014, only involved 23 participants with epilepsy whose treatments also failed them. Seizures experienced by the participants of the said study, who took the drug for three months, dropped by an average of 32 percent.

It is unclear how the extract works in people with epilepsy. Devinsky said that one likely mechanism involved is related to a receptor called GPR55, which could be triggered by cannabidiol and may affect nerve cells' activities.

The new research is set to be presented on April 22 at the American Academy of Neurology's annual meeting in Washington, D.C.