Vagus Nerve

What is VNS Therapy?

(See NOTE below for Bonrich Academy applications that do not require a surgical implant)

  • VNS (vagus nerve stimulation) Therapy consists of an implanted pacemaker-like device that delivers mild, intermittently pulsed signals to the patient’s left vagus nerve, which then activates various areas of the brain.
  • Roughly the size of a small pocket-watch and weighing less than one ounce, the device is implanted in the patient’s left chest area. A thin thread-like wire, attached to the generator, runs under the skin to the left vagus nerve in the neck.
  • The implant procedure typically takes approximately one to two hours.
  • Although the VNS Therapy surgical procedure does not involve the brain, stimulation of the left vagus nerve has been shown to induce widespread bilateral effects in areas of the brain implicated in seizures and mood disorders and responsible for modulation of key neurotransmitters such as serotonin and norepinephrine.
  • Using an external dose adjustment system, physicians can adjust the stimulation duration, frequency and intensity.

Indications for VNS Therapy

  • VNS (vagus nerve stimulation) Therapy is FDA approved as an adjunctive, long-term treatment for chronic or recurrent depression for patients 18 year of age or older who are experiencing a major depressive episode and have not had an adequate response to four or more adequate antidepressant treatments.
  • VNS Therapy was previously approved in the U.S. in 1997 as an adjunctive therapy for reducing the frequency of seizures in adults and adolescents over 12 years of age with partial-onset seizures which are refractory to antiepileptic medications.
  • VNS Therapy is currently approved for sale as a treatment for epilepsy in all the member countries of the European Union, Canada, Australia and other markets. VNS Therapy System is also approved for sale in the European Union (March 2001) and in Canada (April 2001) as a treatment for depression in patients with treatment-resistant or treatment intolerant major depressive episodes including unipolar depression and bipolar disorder (manic depression).
  • VNS Therapy will soon be available in many major cities. It will be available first in cities where the clinical studies were conducted including Dallas, Houston, Charleston, San Francisco, Chicago, and New York among others.
  • VNS Therapy is at various levels of investigational clinical studies as a potential treatment for anxiety disorders, Alzheimer’s disease, bulimia and chronic headache/migraine.

VNS Therapy Clinical Studies in Depression

  • In 2003 and 2004, clinical studies were concluded in the United Sates to support the approval of VNS Therapy for the adjunctive long-term treatment of chronic and recurrent depression. Results from these studies were incorporated into a PMA-Supplement applications submitted to the FDA for approval on October 27, 2003. An amendment to this submission was made in September 2004 with additional long-term data.
  • For many patients, VNS Therapy offers significant improvements in physical, mental and emotional well-being, vitality and social interaction. [1]
  • Clinical study results indicate VNS Therapy has the potential to provide relief to those with longstanding depression which has not responded to other antidepressant therapies. [2] Study results also show that patients who use VNS Therapy may continue to show clinical improvement in both their depression symptoms and quality of life over time. [3]
  • Results from clinical trials indicate that VNS Therapy is not associated with sexual dysfunction or memory impairment. Animal studies also reveal no evidence of impaired fertility or harm to the fetus due to VNS Therapy. Sleep disturbance and weight gain (commonly reported with other antidepressant treatments) have been reported by less than two percent of patients receiving VNS Therapy.
  • Because VNS Therapy is not a drug, it produces no drug interactions with concurrent antidepressant medications.

VNS Therapy Experience in Epilepsy

  • To date, more than 30,000 patients worldwide have accumulated over 79,000 patient years of experience using VNS Therapy.
  • The implant procedure does not involve the brain and is a short outpatient procedure. There is a very low incidence rate of minor complications.
  • VNS Therapy has been proven to effectively decrease seizures. [4] Many physicians and patients report that the quality of life is improved by the reduction in frequency and severity of seizures. [5]
  • VNS Therapy provides seizure reduction and quality-of-life benefits that improve over time. [6]
  • Common Side Effects with VNS Therapy (See NOTE below. Bonrich applied method eliminates side-effects)
  • The common side effects associated with VNS Therapy include hoarseness, sore throat, shortness of breath and coughing. [7]
  • Side effects typically occur only during stimulation and typically diminish over time [8].

VNS Downloads

VNS Alters Brain Blood Flow
Vagus Nerve Stimulation Shows Progress in Stroke Patient Recovery
VNS Neuropsychopharmacology Reviews 2010

More Information

For more information regarding VNS Therapy, its indications, contraindications, warnings and precautions, please call Cyberonics at 1-877-NOW-4-VNS or visit their Web site at

  1. Marangell L., Rush AJ, George M, et al. “Vagus Nerve Stimulation (VNS) for Major Depressive Episodes: One Year Outcomes.” Biological Psychiatry; 2002. (51)4:284, 285–86.
  2. Rush AJ, George M, Sackeim HA, Marangell L, et al. “Vagus Nerve Stimulation (VNS) for Treatment-Resistant Depressions: A Multicenter Study.” Biological Psychiatry; 2000. (47);4:276-286.
  3. Marangell L., Rush AJ, George M, et al. “Vagus Nerve Stimulation (VNS) for Major Depressive Episodes: One Year Outcomes.” Biological Psychiatry; 2002. (51)4:284, 285–86.
  4. Kaakaji W, Geller EB, Bingaman WE. “Vagal Nerve Stimulation for the Treatment of Refractory Seizures: A Preliminary Experience.” Poster #1360 Presented at the 1999 American Association of Neurological Surgeons Meeting.
  5. Tatum WO, Johnson KD, Goff S, et al. “Vagus nerve stimulation and drug reduction.”Neurology; 2001. (56)4:562.
  6. Morris G, Mueller W. “Long-term treatment with vagus nerve stimulation in patients with refractory epilepsy.” Neurology; 1999. (53)7:1733–34.
  7. “Physician’s Manual: VNS Therapy Pulse Model 102 Generator.” Houston, TX: Cyberonics, Inc; 2003.
  8. “Patient’s Manual for Vagus Nerve Stimulation with the NeuroCybernetic Prosthesis (NCP®) System,” page 27. Produced by Cyberonics, October 2000.

NOTE: Bonrich Academy teaches a topical method of VNS that eliminates any “side-effects” and therefore does not require a surgically implanted device. See or contact:

This article courtesy of Butler Hospital, Providence, RI.