Successful cannabinoids in epilepsy therapy
The use of the cannabis ingredient cannabidiol (CBD) seems to mean a reduction in the frequency of seizures in children and adolescents with therapy-resistant epilepsy. However, it is important to wait until further studies are evaluated.
Epilepsy is usually treated with anti-epileptic drugs that contain valproate or carbamazepine as the active ingredient. 20 to 30% of those affected are considered resistant to therapy if they do not respond to at least two therapy attempts with antiepileptics. The cannabis ingredient cannabidiol (CBD) could bring hope to these patients. In preclinical studies, naturally occurring cannabinoids showed anticonvulsant effects that are mediated in the body via the endogenous cannabinoid system.
The safety and effectiveness of cannabinoids as an adjunctive therapy for therapy-resistant epilepsy have now been examined in a review. Included were studies published between 1980 and 2017 in which herbal and pharmaceutical cannabinoids were administered for the therapy or prophylaxis of epilepsy or epileptic seizures. The subjects included all ages and all types of epilepsy. 36 studies were evaluated. In addition, ten ongoing studies were found, the results of which have not yet been published.
The participants were on average 16 years old and had rare and severe forms of epilepsy that could not be treated with conventional medication. In many cases it was found that cannabinoids significantly reduced the frequency of seizures, in some patients by around 50%, and in 10% of those affected the seizures never occurred. The quality of life also improved in 50% of the patients. The tolerance to weak to moderate antiepileptics was generally good. The risk of side effects such as drowsiness, dizziness and diarrhea was slightly increased compared to placebo. Serious side effects were rare with CBD (2.2%), but twice as often as with placebo.
Cannabinoids were used as additional medication in the studies. The study authors therefore do not currently recommend using cannabinoids as a substitute for common antiepileptics. To do this, the results from the current studies would first have to be awaited. (sb, pm)