Overview
Vagus nerve stimulation is a treatment in which sequences of small electrical shocks are applied to the vagus nerve on the left side of the neck. This reduces seizures in some patients, but evidence is inconclusive about how this positive effect is achieved.
The electrical pulses come from a silver dollar-sized battery that is implanted under the skin of the chest. Thin wires from the stimulator are threaded under the skin and wrapped around the vagus nerve in the lower neck.
Vagus nerve stimulation has advantages: It is not a medication that patients must remember to take, nor does it cause common medication side effects such as dizziness, sleepiness or depression. Although surgery is required for the implant, it is usually performed on an outpatient basis and does not pose the risks of epileptic brain surgery.
Disadvantages of vagal nerve stimulation: It may cause hoarseness during periods of stimulation, and no definitive evidence exists that it is significantly more effective than medication. Randomized clinical studies of vagus nerve stimulation in patients with uncontrolled epilepsy clearly show that it can reduce seizures, though patients rarely become seizure-free. Trials also have shown that a sizable group of patients do not experience significant relief from seizures.
For patients who have failed many medications and are not candidates for epilepsy brain surgery, vagus nerve stimulation might be a helpful option. The stimulator and its implantation costs more than $20,000.