Responsive neurostimulation for the treatment of seizures that do not respond to medication.

Efstathia Tzatha, MD Steven C. Karceski, MD In the last 18 years, 12 new antiseizure medications have been discovered. Although there are more medications, there have been no medicines that are clearly better than the older ones. To be clear, the newer medicines do not seem to be any more effective at stopping seizures than the older ones. Studies have shown that about one-third of people with epilepsy have seizures that do not respond to antiseizure medication. A doctor will call the person’s seizures refractory if they have tried 2 or more antiseizure medications, and their seizures have not stopped. Although the newer medicines do not seem to be more effective than the older ones, generally speaking, they seem to cause fewer side effects. Despite this, many patients have difficulty tolerating the high doses that are needed to control their seizures. Because of this, there has been increasing interest in devices that can help to control seizures. One device, the vagus nerve stimulator (VNS), is already available. It was approved for use by the US Food and Drug Administration (FDA) in 1997 for the treatment of refractory epilepsy. Other devices are being studied now, including the responsive cortical stimulator (also known as the responsive neurostimulator or RNS), as discussed in this Patient Page.