Cannabidiol reduced the frequency of convulsive seizures compared with placebo in Dravet syndrome, a childhood epilepsy disorder with a high mortality rate and no approved treatment in the United States, reported a clinical trial in the New England Journal of Medicine
The study randomly assigned 120 children and young adults with the syndrome and drug-resistant seizures to receive either cannabidiol (20 mg/kg of body weight per day) or placebo, in addition to standard antiepileptic treatment.
The median frequency of convulsive seizures decreased significantly over the 14-week trial period only in the cannabidiol group (12.4/mo-5.9/mo vs 14.9/mo-14.1/mo for placebo). Forty-three percent of patients achieved at least a 50% reduction in convulsive-seizure frequency with cannabidiol as opposed to 27% with placebo.
Serious adverse events were more common in the cannabidiol group (16%) than in the placebo group (5%). However, some adverse effects of cannabidiol may have resulted from interactions with other antiepileptic drugs, noted the authors.