Does TMS therapy work? For many people whose depression has not responded to antidepressants, yes, and the research shows how many. The FDA cleared transcranial magnetic stimulation (TMS) for major depressive disorder in 2008 on the strength of sham-controlled trials, and more than a decade of real-world outcome data has followed. What the evidence does not support is an unqualified "TMS works." Outcomes vary from person to person, the numbers depend on how you define success, and the people who benefit most share a recognizable profile.
Start with the definitions, because every statistic below depends on them.
What "Works" Means: Response vs. Remission
Depression research measures success on rating scales, and two thresholds matter.
Response means a meaningful reduction in symptoms, usually defined as a 50% or greater drop in the score on a standard depression scale. Someone who responds feels noticeably better but may still have symptoms.
Remission means the score falls below the scale's cutoff for depression. Symptoms are largely gone. Remission is the goal of treatment, and it is the harder bar to clear.
Two more details shape every TMS success rate you will read. The scale matters: clinician-rated scales and patient questionnaires produce different numbers for the same group of people. And the population matters. TMS is studied almost entirely in people whose depression has already failed to respond to medication, so its rates should be compared with other treatments for that same group, not with a first antidepressant.
What the Clinical Evidence Shows
One of the key trials confirming TMS's effect was a randomized, sham-controlled study led by Mark George and published in Archives of General Psychiatry in 2010. It enrolled 199 adults with major depression who were not taking antidepressants, with 190 included in the analysis. During the blinded phase, 14.1% of people receiving active TMS reached remission, compared with 5.1% receiving sham stimulation. The odds of remission were 4.2 times higher with real treatment, and the number needed to treat was 12.
Those figures look modest next to many TMS marketing pages. The blinded phase was short, the remission bar strict, and a sham-controlled design exists to prove an effect is real, not to show the best a treatment can do in practice. On that goal, it succeeded.
Real-world outcomes come from a different kind of study. In 2012, Linda Carpenter and colleagues published a multisite observational study in Depression and Anxiety covering 307 outpatients treated at 42 clinical TMS practices across the United States. These patients had already tried an average of 2.5 antidepressants at adequate dose and duration without satisfactory improvement. By the end of treatment, 58% had responded and 37.1% were in remission on the clinician-rated scale. On the PHQ-9, a self-report questionnaire, 56.4% responded and 28.7% reached remission.
Our own framing for patients is deliberately conservative: roughly half of people respond and roughly one in three reach remission, and those figures describe people who had not benefited from four or more antidepressants. So how effective is TMS for depression? For depression that has resisted medication, it helps about half of the people who complete a standard course, and it clears depression for about a third.
One clarification about higher numbers you may have seen. Remission rates of 70% or 80% come from newer accelerated protocols, many sessions per day over about a week guided by brain imaging, in small early trials. The FDA has cleared a rapid-acting form of TMS, as the National Institute of Mental Health notes, but we do not offer accelerated protocols, and the figures in this article describe the standard daily course our clinics provide.
TMS Compared to Other Depression Treatments
Antidepressant medication remains first-line, and TMS is typically considered after it. Compared with switching to yet another medication, TMS acts on the brain directly rather than through the bloodstream, which is why it does not cause weight gain, sexual side effects, or sedation.
Electroconvulsive therapy (ECT) produces larger and faster symptom reduction in head-to-head research, but it requires general anesthesia and can affect memory around the time of treatment, so it is reserved for severe or urgent situations. Esketamine (Spravato) and ketamine can act within days rather than weeks, with a different monitoring burden and a different side-effect profile. None of these is universally better. They suit different clinical pictures, and we compare each pairing in depth in dedicated articles.
Who Is Most Likely to Benefit
The evidence points to a consistent profile of the person who does well with TMS. It matches the eligibility criteria we use, which also track what insurers require for authorization:
- A confirmed diagnosis of major depressive disorder. TMS is cleared for MDD, not for every kind of low mood, and getting the diagnosis right comes first. If you are unsure how your diagnosis fits, our guide to major depressive disorder vs. persistent depressive disorder explains the distinction.
- Multiple antidepressants from different classes that did not bring adequate improvement.
- Psychotherapy that was tried and did not bring enough relief.
- No medical contraindications. TMS uses a strong magnetic field, so we screen for a history of seizures or epilepsy, metal in the head outside the mouth, implanted devices such as pacemakers, and a history of stroke, neurosurgery, or brain injury. Pregnancy calls for individualized planning with your obstetric and psychiatric team. Ordinary dental fillings are not a problem.
- The ability to commit to a daily session schedule for several weeks.
Notice what is not on the list: how many years you have spent on medication. More than half of the Carpenter study's patients responded after multiple failed medication trials.
How Long It Takes to See Results
TMS is cumulative. A single session produces nothing you would notice; the benefit builds as repeated stimulation changes activity in the mood circuits being targeted. At our clinics, a full course of TMS means 20 to 30 weekday sessions over roughly four to six weeks.
When improvement shows up varies. Some people notice sleep, energy, or concentration shifting in the second or third week, often before their mood lifts. Others feel little change until the final stretch of the course. Both patterns are normal, and neither predicts the final outcome well, which is why progress is judged with symptom rating scales rather than a mid-course impression. The most common mistake is writing TMS off after a handful of sessions.
What Happens If TMS Doesn't Work?
It is a fair question to ask before you start, and the answer is not "you are out of options."
If symptom scores have not moved by the later part of the course, a psychiatrist reassesses rather than simply stopping. The treatment plan can be adjusted, including the stimulation parameters or the length of the course. Medication can be changed or added, since TMS and medication are often combined. Psychotherapy can be intensified. And other options for treatment-resistant depression remain on the table, including esketamine and, for severe or urgent depression, ECT.
Partial response is its own category: a 30% drop in symptoms is not a treatment failure, and it often shapes what comes next. People who responded well to a first course can also be treated again if depression returns.
What happens if TMS doesn't work is, in the end, what happens at every stage of treating difficult depression: the plan changes, and the person stays in care. If you are having thoughts of suicide at any point, call or text 988 to reach the Suicide and Crisis Lifeline.
What TMS Does Not Do
TMS is a specific tool, and its limits are as well defined as its strengths.
It does not work for everyone. About half of people with medication-resistant depression respond, which means about half do not.
It is not a first-line treatment. In practice, and in insurers' criteria, TMS comes after antidepressant trials, not instead of them.
It is not a general-purpose brain treatment. The FDA clearances are specific: major depressive disorder since 2008 and obsessive-compulsive disorder since 2018, plus a small number of narrowly defined uses. Anxiety disorders and PTSD are being studied, but those uses are not cleared. At our clinics we currently provide TMS for major depressive disorder.
It is not a cure. Remission is a realistic goal, but depression can return, and TMS belongs inside ongoing care rather than serving as a one-time fix.
What to Expect During a Course of Treatment
The practical side is simpler than most people expect.
Treatment begins with a screening visit of 30 to 60 minutes to confirm the diagnosis, review your treatment history, and check for contraindications. Sessions then run Monday through Friday, 30 to 40 minutes each. You sit in a chair, awake, while a magnetic coil rests against your scalp and delivers pulses in short trains. It feels like tapping. With no anesthesia or sedation, you drive yourself home and go straight back to your day.
Side effects are mostly local and mostly early: scalp discomfort at the coil site and headache, both of which typically clear within the first week. Because nothing enters your bloodstream, TMS does not cause the weight gain, sexual dysfunction, stomach upset, dry mouth, or sedation that antidepressants can. The one serious risk, seizure, is exceedingly rare, and the screening process exists to keep it that way.
Talking to a Psychiatrist About Whether TMS Is Right for You
Population statistics tell you what TMS does for people like you. They cannot tell you what it will do for you. That question gets answered in an evaluation, where a psychiatrist reviews your diagnosis, medication history, health, and goals, and tells you plainly whether TMS is a reasonable next step.
At Amae, TMS is one part of an integrated care model in which psychiatry, therapy, primary care, and peer support come from the same team, so a course of TMS fits into your broader care rather than running alongside it. We provide it in Los Angeles, Los Altos, and San Mateo, all commercial insurance plans are accepted alongside cash pay, and prior authorization is handled by our intake team. To find out where you stand, schedule an evaluation with an Amae psychiatrist.
Frequently Asked Questions
What percentage of people does TMS work for?
In a major multisite real-world study, 58% of patients responded and 37% reached remission on clinician ratings after a standard course. Those patients had already tried an average of 2.5 antidepressants without adequate relief, so the numbers describe treatment-resistant depression, not depression in general. Our own conservative framing is that about half respond and about one in three reach remission.
How soon does TMS start working?
Gradually, over the course rather than after a single session. Some people notice changes in sleep, energy, or focus within the first two or three weeks, while others see improvement only near the end of the four-to-six-week course. Neither pattern reliably predicts the final result.
Does TMS work for everyone?
No. Like every treatment for depression, TMS produces a range of outcomes, and roughly half of people with medication-resistant depression do not respond. That is why a psychiatrist tracks symptoms during the course and adjusts the plan if progress stalls.
Is TMS FDA-approved or still experimental?
TMS is FDA-cleared, not experimental. Clearance for major depressive disorder came in 2008 and for obsessive-compulsive disorder in 2018, both on the basis of controlled clinical trials. Uses such as anxiety disorders and PTSD are still at the research stage and are not cleared.
What happens if TMS doesn't work for me?
A psychiatrist reassesses and lays out next steps. Those can include adjusting the treatment plan, combining TMS with medication changes or psychotherapy, or considering other treatment-resistant depression options such as esketamine or ECT. Not responding to TMS does not mean nothing else will work.
How long do the effects of TMS last?
It varies. Improvement often lasts well beyond the end of the course, some people need a maintenance plan or a repeat course, and the timing differs from person to person. Durability deserves its own discussion, and it is one to have with your psychiatrist as you approach the end of a course.
Citations
- George MS, Lisanby SH, Avery D, et al. Daily left prefrontal transcranial magnetic stimulation therapy for major depressive disorder: a sham-controlled randomized trial. Archives of General Psychiatry. 2010. https://pubmed.ncbi.nlm.nih.gov/20439832/ (Tier 1)
- Carpenter LL, Janicak PG, Aaronson ST, et al. Transcranial magnetic stimulation (TMS) for major depression: a multisite, naturalistic, observational study of acute treatment outcomes in clinical practice. Depression and Anxiety. 2012. https://pubmed.ncbi.nlm.nih.gov/22689344/ (Tier 1)
- Micallef-Trigona B. Comparing the effects of repetitive transcranial magnetic stimulation and electroconvulsive therapy in the treatment of depression: a systematic review and meta-analysis. Depression Research and Treatment. 2014. https://pubmed.ncbi.nlm.nih.gov/25143831/ (Tier 1)
- National Institute of Mental Health. Brain Stimulation Therapies. https://www.nimh.nih.gov/health/topics/brain-stimulation-therapies/brain-stimulation-therapies (Tier 2)
- 988 Suicide and Crisis Lifeline. https://988lifeline.org (Tier 2)
