Vagus Nerve Stimulation (VNS) is a small device, similar to a cardiac pacemaker that is implanted under the skin near the left collar bone.
It is connected via a lead to the vagus nerve in the neck. By stimulating the nerve at regular intervals, it can reduce the frequency and intensity of seizures.
The device may also be activated by the patient or carer placing the special VNS therapy magnet over the device for about a second - if applied at the onset of a seizure; this may interrupt a seizure or reduce its severity.
It can be used alongside other treatments for epilepsy, such as medication and dietary treatments and it is often used for frequent, reoccurring seizures.
Side-effects are usually mild and can almost always be reduced with an adjustment of the settings. Hoarseness, throat discomfort, coughing and swallowing difficulties can be side-effects but these may be intermittent and often settle over time.
Any improvement in seizure control may not be seen until 6 to 12 months after the device has been fitted, with the full effect taking up to 18 months.