Transcranial magnetic stimulation, or TMS, is a non-invasive treatment that uses strong magnetic pulses. These pulses, applied to the scalp, travel through the scalp and the skull to the brain. Depending on the specifics of the treatment, these pulses stimulate underactive areas in the brain or calm overactive areas. Over time, this helps improve neuroplasticity — the ability of the brain to send and receive signals between neurons, allowing it to change and adapt.(1)
One way to understand TMS is to think about mental illness like road construction in the brain. The symptoms of mental illnesses, like depression and anxiety, can be thought of as traffic jams in the brain’s communication networks. These traffic jams are caused by damaged roads and broken stoplights. This blocks signals and impairs connections and communication between different areas of the brain.
TMS is like a roadside construction crew that comes in and fixes these impaired neural connections with both short- and long-term solutions. In the short term, TMS fixes broken lights and improves the flow of communication. Over the long term, TMS helps the brain build new and strengthened roads, or neural pathways, enabling it to communicate more effectively.
What conditions are treated by TMS?
TMS has been shown to be safe and effective in treating depression and other mental health conditions. TMS was first approved by the U.S. Food and Drug Administration (FDA) in 2008 for the treatment of major depressive disorder. Since then, the FDA has approved TMS for the treatment of other conditions, including
- Obsessive-compulsive disorder
- Depression with anxious distress
- Migraine headaches
- Short-term smoking cessation. (1-3)
Additionally, while the FDA has not formally approved TMS for the treatment of bipolar I and bipolar II disorders, it has given TMS a “breakthrough device designation.” This means FDA recognizes its potential to treat bipolar-spectrum mental illness and allows for a quicker review process.(3-4)
Is TMS effective?
While antidepressant medications often relieve symptoms in patients with depression, some patients do not fully respond to medication alone. TMS is typically used in combination with medication to help these patients achieve remission (significant reduction or absence of depressive symptoms). In those undergoing treatment for depression, one in two patients who underwent TMS demonstrated a response, or a significant improvement in clinical symptoms, while one in three patients achieved remission. Furthermore, individuals receiving TMS were five times more likely to achieve remission from depressive symptoms as compared to those not receiving TMS. (5-6)
What does TMS treatment look like?
Before undergoing TMS, patients undergo an evaluation by a psychiatrist to determine if they are good candidates for TMS therapy. People with metal implants in the head, aneurysm clips or coils, cochlear implants, cardiac defibrillators, or a history of epilepsy would not be candidates.(7) If a clinician determines that a patient is a good candidate for TMS, they will then determine the parameters and type of TMS that will be administered.
A standard TMS course involves five treatments per week for four to six weeks. Each treatment lasts between three and 30 minutes. A newer, shorter protocol known as the Stanford Accelerated Intelligent Neuromodulation Therapy (SAINT) protocol can be completed in as little as five days but requires multiple treatments per day.(8)
During the first TMS session, a TMS operator will use a magnetic coil on the scalp to establish the patient’s individual motor threshold, determining the optimal site and level for treatment while limiting potential side effects.(9) After the initial motor threshold is obtained, it may be checked periodically during treatment to ensure that the appropriate parameters are being used, especially if there are medication adjustments or other health changes.
TMS is generally done as an outpatient procedure. There is no need for anesthesia or sedation. Patients can drive to and from their appointments. They can continue most of their usual daily activities without any restrictions.
What are the risks and benefits?
Benefits
- Non-invasive - does not require anesthesia or sedation.
- Outpatient procedure - patients can drive and do most of their usual activities after treatment.
- Limited effects on the body.
- No known cognitive side effects.
- May be beneficial for patients with treatment-resistant depression who have not responded to multiple prior medication trials.
- Many health insurance carriers will cover standard TMS if a patient has not responded to three to four prior antidepressant trials.
Risks - common
- Scalp discomfort during treatment
- Muscle twitching during treatment
- Mild headaches
Risks - uncommon
- Severe headaches
- Syncope (fainting)
- Hearing loss (prevented with earplugs during treatment)
- Seizure (very rare, 1/10,000)
Physician Review
- Sarah Elmer, M.D.
Psychiatry, PGY-3
University of Texas Southwestern Medical Center - Donald Egan, M.D., M.P.H.
Addiction Psychiatry Fellow
University of Texas Southwestern Medical Center
2026