Even though the development of new antidepressant medications in recent years has been a boon to patient suffering from depressive disorders, a substantial number of patients do not respond to currently available treatments.

Transcranial magnetic stimulation, an entirely different approach for the treatment of depression, has recently gained approval from the U.S. Food and Drug Administration (FDA) for use in patients who do not respond to other treatment options.

Clinical trials have reported significant improvement in depression symptoms with TMS.

Transcranial magnetic stimulation (TMS) is the application of short pulses of magnetic energy to the brain. In the case of depression, these pulses are aimed at the area of the brain which controls mood, called the limbic system. When the magnetic pulses hit nerve cells in this area, they cause the nerve cells to become more active. Altering the activity of the cells responsible for mood is thought to improve major depression disorder.

Clinical trials have reported significant improvement in depression symptoms with TMS. Patients also showed improvements in anxiety and physical symptoms, like headache and pain, caused by depression.

These are promising results for patients with major depressive disorder, which can be debilitating when not adequately treated. Currently, patients may be treated sequentially with various medications, with the hopes that one will eventually work to control symptoms. Because each medication takes 4 to 6 weeks to begin working, some patients can go months or years without relief.

Additionally, TMS does not carry the side effects commonly associated with many antidepressants, including sexual dysfunction, weight gain, and sedation. TMS is applied non-invasively through an external device that delivers MRI-strength magnetic pulses. Treatment is daily for 4 to 6 weeks, and is performed on an outpatient basis. Patients are awake during the procedure, which takes about 40 minutes to perform. TMS has not been studied as a first-line treatment for depression, and is currently only approved for use in patients with unipolar, non-psychotic, major depressive disorder that have failed to find relief with at least one other treatment. However, clinical studies are underway to determine if TMS may be useful as an initial treatment options for patients with depression, and for the treatment of other psychiatric disorders.