Why it's done

About one-third of people with epilepsy don't fully respond to anti-seizure drugs. Vagus nerve stimulation may be an option to reduce the frequency of seizures in people who haven't achieved control with medications.

Vagus nerve stimulation may also be helpful for people who haven't responded to intensive depression treatments, such as antidepressant medications, psychological counseling (psychotherapy) and electroconvulsive therapy (ECT).

The Food and Drug Administration (FDA) has approved vagus nerve stimulation for people who:

• Are 4 years old and older
• Have focal (partial) epilepsy
• Have seizures that aren't well-controlled with medications

The FDA has also approved vagus nerve stimulation for the treatment of depression in adults who:

• Have chronic, hard-to-treat depression (treatment-resistant depression)
• Haven't improved after trying four or more medications or electroconvulsive therapy (ECT), or both
• Continue standard depression treatments along with vagus nerve stimulation

Additionally, researchers are studying vagus nerve stimulation as a potential treatment for a variety of conditions, including headaches, rheumatoid arthritis, inflammatory bowel disease, bipolar disorder, obesity and Alzheimer's disease.