Anecdotal reports addressing the successful seizure treatment of severe epilepsies with cannabidiol (CBD) have increased both public interest and academic research. Placebo-controlled, randomized, controlled trials proved the efficacy of pharmaceutical-grade CBD in epilepsy treatment, thus leading to pharmaceutical-grade CBD approval by the US Food and Drug Administration and the European Medicines Agency for the treatment of seizures in Dravet syndrome and Lennox–Gastaut syndrome as well as for tuberous complex syndrome by the Food and Drug Administration only. However, the CBD market is confusing because an array of products of different origins, purity, and concentration is available. Additionally, the results from the pivotal studies with plant-derived, pharmaceutical-grade CBD cannot simply be transferred to other epilepsy types or CBD of any origin. Because of the high demands and expectations that patients with epilepsy and their caregivers have regarding CBD, information outlining the proven facts and potential risks is essential. The aim of this article is to thoroughly review available research data and practical recommendations to provide the treating physician with the necessary information for counseling patients with epilepsy.
Transcutaneous auricular vagus nerve stimulation (taVNS) is a novel non-invasive brain stimulation technique considered as a potential supplementary treatment option for subjects with refractory epilepsy. Its exact mechanism of action is not yet fully understood. We developed an examination schedule to probe for immediate taVNS-induced modifications of large-scale epileptic brain networks and accompanying changes of cognition and behaviour. In this prospective trial, we applied short-term (1 h) taVNS to 14 subjects with epilepsy during a continuous 3-h EEG recording which was embedded in two standardized neuropsychological assessments. From these EEG, we derived evolving epileptic brain networks and tracked important topological, robustness, and stability properties of networks over time. In the majority of investigated subjects, taVNS induced measurable and persisting modifications in network properties that point to a more resilient epileptic brain network without negatively impacting cognition, behaviour, or mood. The stimulation was well tolerated and the usability of the device was rated good. Short-term taVNS has a topology-modifying, robustness- and stability-enhancing immediate effect on large-scale epileptic brain networks. It has no detrimental effects on cognition and behaviour. Translation into clinical practice requires further studies to detail knowledge about the exact mechanisms by which taVNS prevents or inhibits seizures.