Transcranial Magnetic Stimulation

Transcranial magnetic stimulation is a relatively new medical treatment that can be used in certain cases of depression. During the treatment, a large magnetic device (electromagnetic coil) is used to send low-intensity electric pulses from the surface of your head, through your scalp and skull, to stimulate your brain. The mode of action of transcranial magnetic stimulation is not known. However, the electric stimulation somehow affects the mood centers in the brain to improve depressive symptoms in some patients. Not all health insurance plans cover transcranial magnetic stimulation in the treatment of depression. Be sure to check your health insurance plan before choosing this treatment.

Transcranial magnetic stimulation typically is only used in the treatment of severe depression, when treatment with antidepressant medication or talk therapy (psychotherapy) or both has not worked. Transcranial magnetic stimulation has advantages over other treatments for depression that involve use of electric stimulation. Transcranial magnetic stimulation does not require the use of medicine to make you sleep (general anesthetic) like vagal nerve stimulation and deep brain stimulation do. Transcranial magnetic stimulation delivers electric stimulation at a much lower intensity than shock therapy (electroconvulsive therapy). The higher intensity electric stimulation is frequently associated with posttreatment confusion and sometimes permanent memory loss.

Transcranial magnetic stimulation may not be effective in the following cases:

  • Depression associated with bipolar disorder.

  • Depression associated with psychosis.

  • Depression associated with thoughts of suicide.

  • Depression that lasts longer than 4 years

  • Depression that has not responded to treatment with electroconvulsive therapy.

Additionally, transcranial magnetic stimulation should not be used by pregnant women or by people who are who have any metal devices in their bodies from surgeries such as a hip or knee replacements.


Transcranial magnetic stimulation usually is done in a clinic or your caregiver's office. You will be awake and alert during treatments. Usually, treatments are 5 days per week for 4 to 6 weeks. Each treatment takes about 40 minutes. At your initial visit your caregiver must determine the appropriate strength of electric pulses for your treatment by gradually increasing the electrical pulses until your fingers or hands twitch.

During the procedure you will sit in a comfortable chair. An electromagnetic coil is placed against your head. The magnet is aimed at the left front part of your brain. That area of the brain is not as active as it should be in people who have depression. During the treatment, you may hear a clicking noise. You also might feel some gentle tapping on your head or mild scalp discomfort.


Common side effects from transcranial magnetic stimulation generally are mild and last for a short time after each treatment. They typically improve after the first week or two of treatment and include:

  • Headache or a feeling of lightheadedness.

  • Scalp discomfort at the site of stimulation.

  • Twitching or tingling of your scalp.

  • Discomfort from noise during treatment (if ear protection is not used).

Serious side effects are rare. They can include:

  • Seizures, particularly in people who have epilepsy or a history of seizures.

  • Mania, particularly in people who have bipolar disorder.

  • Hearing loss due to inadequate ear protection during treatment.