What Is TMS Therapy? Everything You Need to Know About Brain Stimulation for Depression

After two failed antidepressants, the clinical conversation changes. You are no longer asking which SSRI to try next. You are asking whether medication is the right path at all, and what comes after it if it is not.

Transcranial magnetic stimulation is one of those answers. Not a new one: the FDA cleared it for major depressive disorder in 2008. Not a last resort: it is commonly used after a single failed medication trial. Not invasive: no surgery, no anesthesia, no memory effects, and patients drive themselves home afterward.

But it is still widely misunderstood, and people considering it often have questions that the basic explainers do not answer: how it actually works, whether it will work for them, what a session is like, and how it fits into the broader treatment picture.

This is the complete answer.

What This Page Covers

• What TMS therapy is and how it works
• The FDA clearance history and what it covers
• What a TMS course looks like: sessions, frequency, duration
• Who responds and who is not a good candidate
• How TMS compares to ECT and medication
• Cost, insurance, and coverage considerations
• How SiggyMD approaches the treatment-resistant depression conversation

What TMS Therapy Is

Transcranial magnetic stimulation uses an electromagnetic coil placed on the scalp to deliver focused magnetic pulses to specific regions of the brain. TMS uses an electromagnetic coil as a noninvasive device to target underlying brain regions. Noninvasive means there is no need for any surgery or even breaking the overlying skin to reach the brain.

The target for depression is the dorsolateral prefrontal cortex (DLPFC): a region of the brain’s frontal lobe that regulates mood, executive function, and emotional response. In depression, this area tends to be underactive. The dorsolateral prefrontal cortex is one of the major control centers of the brain, and its stimulation is thought to enhance its control of various symptoms of depression.

When the TMS coil delivers a magnetic pulse, it induces a small electrical current in the neurons of the DLPFC, stimulating neural activity. Repeated stimulation over the course of treatment promotes synaptic plasticity, new neural connections, and normalization of mood circuitry. Neuronal physiology that responds to TMS is of central importance, as repetitive stimulations increase synaptic plasticity, causing it to last longer even after stimulation ceases.

The effect accumulates over days and weeks, which is why a course of treatment is required rather than a single session.

FDA Clearance: What TMS Is Approved For

TMS was approved by the FDA in 2008 for the treatment of major depressive disorder. Since then, its cleared indications have expanded.

Current FDA-cleared indications for rTMS (repetitive TMS) in the United States include:

Major depressive disorder in adults who have failed to achieve satisfactory improvement from prior antidepressant medication. OCD (obsessive-compulsive disorder). Smoking cessation (for certain devices). In 2025, the FDA also cleared an accelerated deep TMS protocol for major depressive disorder.

TMS for other conditions including bipolar depression, PTSD, and chronic pain is used off-label in research settings. There are currently large clinical trials looking at the effectiveness of TMS in conditions such as pediatric depression, bipolar disorder, and PTSD. While these are promising avenues, TMS for these conditions is not yet approved and would be considered off-label.

What a TMS Course Looks Like

Session Format

During a session, the patient sits in a reclined chair and remains fully awake. The treating team places the TMS coil over the scalp at the location corresponding to the DLPFC. You may hear a clicking sound or feel tapping sensations as the device delivers focused magnetic stimulation to the front portion of your brain. The entire appointment typically lasts around 15 minutes.

The sensation varies: most patients describe a light-to-moderate tapping or knocking feeling at the scalp. It is not painful for most patients, though some experience mild discomfort that diminishes over the first several sessions.

Session Frequency and Duration

A common schedule is five days a week for four to six weeks, often about 30 to 36 sessions for depression-related protocols. Standard high-frequency rTMS sessions last 20 to 40 minutes each.

Newer protocols, particularly theta-burst stimulation (TBS or iTBS), deliver pulses in short, rapid bursts. A 3-minute theta burst protocol has been shown in a large randomized trial of 414 participants to be not statistically inferior to 37.5 minutes of high-frequency rTMS. Theta-burst protocols are increasingly standard at TMS centers and significantly reduce session time without compromising efficacy.

Some accelerated programs deliver multiple short sessions per day over about five days, shortening the overall treatment timeline in certain centers. Stanford’s SAINT protocol, an accelerated theta-burst approach, has produced rapid remission in some patients, though it requires specialized infrastructure.

After completing a standard course, some patients receive maintenance sessions: a few sessions per week tapering over time, or retreatment triggered when early signs of relapse appear. A 2024 continuation therapy study found that 86% of participants maintained remission over 12 months when retreatment was triggered by early warning signs, with most retreatment courses requiring only 1 to 2 days.

How Effective Is TMS?

Effectiveness data for TMS comes primarily from its use in treatment-resistant populations, meaning patients who have not responded to antidepressants.

TMS is successful for about 50 to 60% of patients with treatment-resistant depression. Of those who respond, approximately half achieve full remission.

About 60% of people who didn’t respond to other depression treatments respond to standard TMS protocols, and more than half of these patients stay in remission at six-month follow-up appointments after stopping TMS.

A 2023 meta-analysis found that rTMS had a large effect size advantage over sham stimulation for depression (Hedges’s g = 0.791). Effect sizes vary across studies, and some systematic reviews have noted concerns about publication bias and heterogeneity in the literature. The evidence is strongest for patients with treatment-resistant depression who have documented prior medication failures.

TMS generally produces better response rates in patients with lower degrees of treatment resistance. Its use as a first-line treatment before any medication trial has very limited evidence.

Side Effects and Safety

TMS has a favorable safety profile compared to most pharmacological alternatives and to ECT.

Common side effects include headache during or after treatment and scalp discomfort at the coil site. Both are typically mild and diminish as treatment continues. TMS is as safe as having an MRI and does not involve radiation.

Serious side effects are rare. A rare but serious side effect is seizures. TMS may not be appropriate for people with epilepsy, a history of head injury, or those at high risk due to other neurological conditions. Seizure risk is approximately 0.1% and is most often attributable to protocol deviations or risk factors that should have precluded treatment.

No memory loss. This is a common fear because TMS is sometimes confused with ECT, which does cause memory effects. TMS does not. TMS offers brain stimulation without the ECT side effects of confusion and short-term memory loss.

Who Should Not Receive TMS

TMS is contraindicated for patients with:

Metal implants in or near the skull, such as aneurysm clips, cochlear implants, or surgical hardware in the head and neck region. Standard dental work including fillings and braces is not a contraindication.

A history of seizure disorders. The magnetic stimulation carries a small risk of lowering the seizure threshold.

Certain cardiac pacemakers or deep brain stimulators, depending on device type and placement.

Pregnancy is a relative consideration. TMS is prescribed and administered by a TMS-trained psychiatrist who conducts a full screening before recommending treatment.

TMS vs. ECT: What’s the Difference?

Both are brain stimulation treatments for depression, but they are fundamentally different procedures.

	TMS	ECT
Mechanism	Magnetic pulses to the scalp	Electrical current to induce a controlled seizure
Anesthesia	Not required	Required
Memory effects	None	Significant short-term, some long-term
Outpatient	Yes, daily appointments	Requires monitoring post-procedure
Efficacy in TRD	50 to 60% response	Higher for severe/psychotic depression
Recovery time	None, drive yourself home	Several hours recovery
Availability	Many outpatient TMS centers	Hospital-based, less widely available

For most patients with treatment-resistant depression who have not had psychotic features, TMS is tried before ECT. ECT remains a viable option for the most severe presentations, particularly those with acute suicidality or psychotic depression, where faster results matter more than side effect profile.

Cost and Insurance

Most major insurance plans cover TMS for major depressive disorder when the patient has documented prior antidepressant failures. Most insurance companies cover that basic series of 30 treatment sessions for the treatment of depression.

Medicare began covering an accelerated TMS protocol in 2025. Cash-pay costs for a standard course typically range from $6,000 to $12,000 depending on the number of sessions and provider. The prior authorization process for insurance typically requires documentation of at least one prior antidepressant trial.

Insurance coverage for TMS in conditions other than depression is limited in most cases, as off-label use is generally not covered.

How SiggyMD Approaches Treatment-Resistant Depression

SiggyMD’s clinical model is designed around ongoing monitoring that provides exactly the longitudinal data that informs treatment escalation decisions. When daily check-ins show that mood is not improving after six to eight weeks on a therapeutic dose, the prescriber can see that trend and initiate a clinical conversation about next steps before the patient reaches full treatment resistance.

TMS is outside SiggyMD’s direct clinical scope. What SiggyMD provides is the medication management, adherence monitoring, and clinical oversight that helps most patients achieve response before they need interventional options. For patients who are already treatment-resistant, the intake process captures that history, and a licensed prescriber reviews it to determine the appropriate path.

“Treatment resistance is not a ceiling,” says Daniel Montville, MD, Psychiatrist, of the SiggyMD clinical team. “It is a signpost that tells me to change direction. That might mean a different medication class, augmentation, or a referral for TMS. The earlier I have visibility into what is and is not working, the more options we have before the window for each approach closes.”

For context on depression medication management and what comes after a first-line trial, read our guide to how depression treatment decisions are made.

What Members Are Saying

AL

A.L., 52

Treatment-Resistant Depression

“I had been depressed for eight years and tried four different medications. My psychiatrist referred me for TMS after the fourth. By week five I could feel something shift. By the end of the course, I was functioning in ways I had not in a decade. I did not understand what it was doing to my brain, but I could feel it working.”

BM

B.M., 39

Major Depressive Disorder

“The thing no one told me is how easy it is. You sit in a chair. You are awake. You drive home. There is a tapping feeling and a clicking sound. After six weeks my prescriber said my PHQ-9 score had dropped by more than half. That is not a small change.”

Member stories reflect real experiences. Names and identifying details have been changed to protect privacy. Results vary. SiggyMD is currently invite-only.

Understanding Your Full Range of Options

TMS is not for everyone. It is most appropriate for patients who have documented medication failures and are looking for the next evidence-based step. For patients who have not yet tried medication, or who have only tried one antidepressant at a subtherapeutic dose or duration, medication management comes first.

Understanding the full treatment path for depression helps you and your prescriber make decisions at the right moments rather than after the window for simpler interventions has closed. Or start your anonymous intake with SiggyMD today to talk to a licensed clinician about where you are in your treatment journey.

Sources

1. Garakani A, et al. Pharmacotherapy for Anxiety Disorders: From First-Line Options to Treatment Resistance. Frontiers in Psychiatry. 2021;11:595584.

2. Trevizol AP, et al. Use of Transcranial Magnetic Stimulation for Depression. Harvard Review of Psychiatry. 2019;27(4):216-232.

3. Kiebs M, et al. Repetitive transcranial magnetic stimulation in non-treatment-resistant depression. British Journal of Psychiatry. 2019;215(2):445-446.

4. Yale Medicine. Transcranial Magnetic Stimulation (TMS) for Depression, OCD: What to Know. Accessed June 2026.

5. Cleveland Clinic. TMS (Transcranial Magnetic Stimulation): What It Is. Accessed June 2026.

6. Harvard Health. Transcranial magnetic stimulation (TMS): Hope for stubborn depression. 2018.

7. VA Montana. Transcranial Magnetic Stimulation Treatment for Depression. Accessed June 2026.

8. University of Utah Health. Transcranial Magnetic Stimulation (TMS). Accessed June 2026.