"So is that it? Is there nothing left to try?" The woman sitting across from me was in her early forties, holding prescription bags from three different hospitals. The first antidepressant left her too nauseated to eat. The second she persisted with for three months; her mood levelled out, but she spent the days in a fog. The sixth month on her third medication, she told me the strongest thing she felt was nothing at all.
She did not ask that question in distress. She asked it calmly, in the flat voice of someone who has stopped expecting an answer. I have seen that particular calm many times, and it usually means the person has quietly put their hopes away rather than stopped hurting.
If you have arrived at that point, here is the first thing worth saying: inadequate response to antidepressants is a defined clinical state with a name and a set of next steps. It is not a personal failure and it is not the end of the list. This article is about one of those next steps, and the one with the strongest evidence base behind it.
What rTMS Actually Is
rTMS stands for repetitive Transcranial Magnetic Stimulation. It is a brain stimulation treatment that requires no anaesthesia, no surgery, and no medication.
The mechanism is straightforward. A coil is positioned against a specific point on your scalp. When current passes through it, the coil generates a rapidly changing magnetic field. That field passes through the skull unimpeded and induces a small electrical current in the cortex beneath, which in turn modulates the activity of neurons in that region. You stay fully awake throughout. You can sit and talk, and you can drive yourself home or return to work immediately afterwards.
One misconception is worth clearing up early. rTMS is not electroconvulsive therapy. People often hear "brain stimulation" and think of ECT, but the two differ in mechanism, intensity, risk profile, and clinical role. A full comparison follows below.
The US FDA cleared rTMS for major depressive disorder in 2008, and Deep TMS in 2013. Devices have been approved for the depression indication in Taiwan since 2018.
Are You Actually Treatment-Resistant?
rTMS is not a first-line treatment for depression. It has a specific place in the sequence.
The most widely used definition of treatment-resistant depression is failure to achieve remission after at least two antidepressant trials of adequate dose and adequate duration within the same depressive episode.
Two words in that sentence carry most of the weight: adequate dose and adequate duration. Patients frequently tell me they have failed five or six medications, and on going through the history it turns out several were stopped after two weeks because of side effects, or were never titrated past the starting dose. Strictly speaking those are not failed trials, they are unfinished ones. Before considering rTMS, the first task is to lay out the medication history properly and find out which category you are actually in.
The STAR*D study, which followed more than three thousand patients with depression, found remission rates falling at each successive step: roughly 37% at the first medication, 31% at the second, 14% at the third, and 13% at the fourth.[7] The practical implication is that the more medications you have cycled through, the less likely the next one is to be the answer, which is precisely when non-pharmacological options become worth considering.
[Table 1] Treatment stages in depression and the reasonable next step
| Stage | Definition | Typical picture | Reasonable next step |
|---|---|---|---|
| First-line | First adequate trial underway | 1 to 2 months into treatment | Complete the trial before judging |
| Partial response | Improved but not in remission | Mood better, function not restored | Optimise dose or augment |
| Treatment-resistant | Two or more adequate trials failed | Multiple switches, little gain | rTMS can be evaluated |
| Acute high risk | Strong self-harm intent, food refusal | Immediate safety concern | Consider admission and ECT |
That last row matters. rTMS takes weeks to produce an effect, which makes it the wrong tool when there is an immediate safety concern.
Why Magnetic Stimulation Affects Mood
Imaging studies in depression converge on a fairly consistent finding: reduced activity in the left dorsolateral prefrontal cortex. That region handles emotional regulation, concentration, planning, and decision-making, which maps closely onto the complaints patients describe as brain fog, loss of drive, and inability to decide anything.
The standard rTMS protocol for depression places the coil over the left DLPFC and delivers high-frequency pulses, usually at 10 Hz, to increase activity there. Some patients instead receive low-frequency inhibitory stimulation over the right DLPFC, or bilateral stimulation, depending on clinical assessment.
What makes this work is that the cortical surface being stimulated is densely connected to deeper limbic structures, the amygdala and hippocampus among them, that govern emotional processing. The effect propagates through those networks rather than stopping at the surface. It also explains why the benefit accumulates over weeks instead of appearing immediately: what changes is the plasticity of a circuit, not the symptom of the moment.
Deep TMS Compared With Standard rTMS
Conventional rTMS uses a figure-of-eight coil, which stimulates a focused area to a depth of roughly 1.5 to 2 cm. Deep TMS uses an H-coil, which reaches a broader area at a depth of around 3 to 4 cm.
Greater depth means more of the emotion-regulating regions fall within range. That said, there is not yet sufficient head-to-head evidence to conclude that Deep TMS outperforms conventional rTMS. Each suits particular situations, and the choice should follow clinical assessment rather than marketing.
What a Course Actually Looks Like
This is what patients ask about most, so it is worth being concrete.
The first session begins with localisation. Your motor threshold is measured by using magnetic pulses to elicit a slight twitch in the thumb, which establishes the stimulation intensity appropriate for you. Skull thickness and cortical distance vary between individuals, so this step ensures the dose is calibrated to you rather than taken from a formula.
Session length depends on the protocol. Conventional 10 Hz sessions run roughly 20 to 37 minutes. Intermittent theta-burst stimulation (iTBS) takes about 3 minutes. The THREE-D trial published in The Lancet in 2018 enrolled 414 patients and established that iTBS is non-inferior to conventional 10 Hz stimulation while taking a fraction of the time.[4]
What it feels like. Most people describe a rhythmic tapping sensation on the scalp, accompanied by a clicking sound from the coil, which is why earplugs are worn. The first few sessions can feel prickly or mildly uncomfortable, and most people have adjusted within a week. You remain awake, you do not need to fast, and you leave immediately afterwards.
How many sessions? International evidence and treatment guidelines consistently recommend 20 to 30 sessions for an acute course, five days a week over four to six weeks.[9]
I state the number explicitly because I do not want anyone finishing ten sessions under the impression that treatment is complete. An inadequate number of sessions is among the most common and most avoidable reasons rTMS appears not to work.
When does it start working? Most patients notice change somewhere between weeks two and four. Often the patient is not the first to notice; family members tend to comment on improved energy before the patient registers a mood shift. Sleep and appetite frequently improve ahead of mood.
What the Evidence Actually Shows
Rather than a flattering headline figure, here is an honest range.
In the most rigorous randomised controlled trials, the numbers look modest. The OPT-TMS trial reported by George and colleagues in 2010 found a remission rate of 14.1% at three weeks, against 5.1% for sham stimulation.[2] O'Reardon and colleagues reported effects of a similar magnitude in their 2007 multisite trial.[1]
Real-world data look considerably better. In a naturalistic observational study of 307 patients published by Carpenter and colleagues in 2012, the clinical response rate reached 58% and remission 37%.[3] The gap exists because controlled trials typically use shorter courses and prohibit concurrent medication changes, whereas in practice rTMS runs alongside medication and courses are extended according to response.
For Deep TMS, the multicentre trial by Levkovitz and colleagues published in World Psychiatry in 2015 reported a week-five response rate of 38.4% against 21.4% for sham, with remission at 32.6% against 14.6%.[5]
[Table 2] rTMS outcomes across different study designs
| Type of evidence | Study | Response rate | Remission rate |
|---|---|---|---|
| Strict controlled trial | OPT-TMS 2010 | About 15% | 14.1% |
| Deep TMS controlled | Levkovitz 2015 | 38.4% | 32.6% |
| Real-world observation | Carpenter 2012 | 58% | 37% |
| One-year follow-up | Dunner 2014 | About 62% sustained | Not reported |
How long does the benefit last? The one-year follow-up study by Dunner and colleagues found that roughly 62% of acute responders still met response criteria twelve months later.[6] Put the other way, about one in three experienced a return of symptoms within the year.
I raise this with every patient before we begin. rTMS is not a one-off cure. Maintenance sessions can be considered if symptoms return, and most patients respond well to retreatment. Framing it as a recalibration rather than a permanent repair sets expectations much closer to reality.
Side Effects and Who Cannot Have It
The principal advantage of rTMS is not that it outperforms medication. It is that it lacks the systemic side effects that cause people to abandon treatment.
No weight gain, no sexual dysfunction, no sedation, no dry mouth or constipation, no discontinuation syndrome. For patients who have repeatedly stopped antidepressants because of how they felt on them, that difference is a practical one.
[Table 3] Common rTMS side effects and management
| Side effect | Frequency | Severity | Management |
|---|---|---|---|
| Scalp discomfort at site | About 30 to 40% | Mild | Adjust coil angle and intensity |
| Headache | About 20 to 30% | Mild | Responds to simple analgesia |
| Facial muscle twitching | Common | Mild | Normal, resolves after session |
| Seizure | Very rare | Serious | Screening substantially reduces risk |
Seizure is the one risk that warrants serious attention, though it remains rare. Under the international TMS safety consensus updated in 2021, risk falls into the rare category when standard safety parameters are observed.[8] This is exactly why pre-treatment screening is not a formality to be skipped.
Contraindications
There is one absolute contraindication: non-removable ferromagnetic metal in or near the head, such as aneurysm clips, cochlear implants, deep brain stimulators, or retained metal fragments. The magnetic field interacts with such material, and there is no room for negotiation on this point.
Relative contraindications require individual assessment: a personal or family history of seizures, significant head injury or prior brain surgery, raised intracranial pressure, an implanted pacemaker or defibrillator, pregnancy (where data remain limited), and states that lower the seizure threshold such as alcohol withdrawal or severe sleep deprivation.
Worth noting, because it comes up constantly in clinic: dental fillings, braces, and orthopaedic metalwork in the spine or limbs are not contraindications.
Choosing Between rTMS, Medication, ECT and Esketamine
Treatment-resistant depression offers more than one route. What matters is understanding where each one sits.
[Table 4] Four treatment options in treatment-resistant depression
| Treatment | Best suited to | Main advantage | Main limitation |
|---|---|---|---|
| Antidepressants | First-line at any stage | Insurance covered, taken at home | Systemic side effects, slow onset |
| rTMS | Two failed trials, side-effect intolerance | No systemic or cognitive effects | Daily attendance, self-funded |
| ECT | Severe, psychotic, or food-refusing | Highest response rate, fastest | Anaesthesia, possible memory effects |
| Esketamine | Resistant cases needing rapid effect | Works within hours to days | In-clinic monitoring, dissociation |
A few practical principles.
ECT still achieves the highest response rates in severe depression, and rTMS has not displaced it. Where there is strong suicidal intent, food refusal, or psychotic features, speed matters more than side effects, and ECT is the appropriate first consideration.
rTMS occupies the middle ground between inadequate medication response and the point at which admission or anaesthesia becomes necessary. It suits patients who are highly sensitive to medication side effects, and those who prefer not to take long-term medication for reasons such as work or breastfeeding.
rTMS is usually added to medication rather than substituted for it. My own practice is medication-led with rTMS as an adjunct, and the combination generally outperforms either alone.
Cost and Insurance Coverage
Taiwan's National Health Insurance does not currently provide routine coverage for rTMS in depression, so the great majority of courses are self-funded. That is a practical reality to factor in before starting.
My fees are as follows:
- Single session: NT$5,000
- The fee includes the motor threshold localisation performed before the first session
As noted above, an acute course typically requires 20 to 30 sessions, so budget on the basis of the full course rather than the price of a single session. I would rather you work the total out before starting than have treatment interrupted halfway through, because a course stopped partway tends to deliver little.
The number of sessions you actually need depends on your response. Some patients reach remission at around 20 sessions; others need the full 30. This is reviewed at intervals during treatment, not revealed at the end.
Frequently Asked Questions
Q1: Does rTMS genuinely work, or is it placebo?
It works, and it has been tested against sham stimulation to establish that. Multiple randomised controlled trials show significantly higher remission rates with active stimulation than with sham.[1][2][5] To be honest about it, though: it does not work for everyone. Real-world response rates sit somewhere between 40% and 60%, which leaves a meaningful proportion of patients with limited benefit.
Q2: Is rTMS painful?
Most people would not call it pain. It is closer to a rhythmic tapping or prickling on the scalp. Around 30 to 40% find the treatment site uncomfortable during the first few sessions, and most adapt within a week. If it genuinely cannot be tolerated, the coil angle or intensity can be adjusted, so there is no need to endure it.
Q3: How many sessions before I see improvement?
A full acute course is 20 to 30 sessions, five days a week for four to six weeks. Most people notice change between weeks two and four. Feeling nothing after ten sessions does not mean the treatment has failed; more often it means the course is not yet complete.
Q4: How is rTMS different from ECT?
Substantially. ECT requires general anaesthesia, induces a controlled seizure, and can affect short-term memory, but achieves the highest response rates in severe depression. rTMS is performed fully awake, needs no anaesthesia, and does not impair memory or cognition, but is less effective in the most severe cases. They are not competing options so much as tools for different levels of severity.
Q5: Do I need to stop my medication during treatment?
Usually not, and I generally advise against it. rTMS is most often delivered alongside medication, and the combination tends to work better than either alone. Any change to medication should be assessed by your treating physician, so please do not stop on your own.
Q6: Is rTMS covered by insurance in Taiwan?
Not routinely at present, so most courses are self-funded. Coverage rules can change with policy, so confirm the current position with the treating institution before beginning.
Q7: What happens if the benefit fades?
It may. One-year follow-up data show about 62% of responders sustaining benefit at twelve months, meaning roughly a third experience some return of symptoms within the year.[6] Maintenance sessions can be considered at that point, and most patients respond well to retreatment. It is more useful to treat this as long-term management requiring periodic review than as a single definitive intervention.
Further reading:
- Does rTMS Help ADHD? Evidence, Attention Benefits and Treatment Limitations
- Depression: Symptoms, Brain Mechanisms, Treatment and When to Seek Help
- Maternal Depression: Symptoms, Causes, Treatment and How Families Can Help
- PHQ-9 Depression Self-Assessment
Dr. Tam's Clinical Perspective
My position on rTMS is consistent: it is a good tool, it is not a miracle, and it should not be sold as the last resort after medication has failed.
If you are weighing it up, a few things are worth doing first.
Confirm that you have genuinely completed the medication step. Write out your history: which medication, at what dose, for how long, and why it stopped. A surprising number of cases labelled treatment-resistant turn out to be incompletely treated. This takes ten minutes and may save you a considerable sum.
Budget the whole course, not the first few sessions. Five days a week for four to six weeks. Can you take the time? Is the travel manageable? Can you cover 20 to 30 sessions? A course abandoned midway achieves little, so this is realistic planning rather than discouragement. Do not stop your current medication either, since the combination generally outperforms either treatment alone.
Set your expectations accurately. A response rate between 40% and 60% means a real proportion of people gain limited benefit. Even among responders, about a third need further treatment within a year. Knowing this does not reduce the chance of success, but it does make it less likely you will abandon a working treatment out of disappointment.
If you have immediate safety concerns, rTMS is not the right choice. Strong suicidal thoughts need a faster intervention. Please seek urgent medical care or go to an emergency department.
There is no single answer in the treatment of depression. Medication, psychotherapy, rTMS, and changes to how you live all have a place. What matters is finding the combination that fits where you are now, rather than believing any one of them will do the whole job.
References
- O'Reardon JP, Solvason HB, Janicak PG, et al. Efficacy and Safety of Transcranial Magnetic Stimulation in the Acute Treatment of Major Depression: A Multisite Randomized Controlled Trial. Biological Psychiatry. 2007;62(11):1208-1216. DOI · PubMed
- 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;67(5):507-516. DOI · PubMed
- 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;29(7):587-596. DOI · PubMed
- Blumberger DM, Vila-Rodriguez F, Thorpe KE, et al. Effectiveness of Theta Burst Versus High-Frequency Repetitive Transcranial Magnetic Stimulation in Patients with Depression (THREE-D): A Randomised Non-Inferiority Trial. The Lancet. 2018;391(10131):1683-1692. DOI · PubMed
- Levkovitz Y, Isserles M, Padberg F, et al. Efficacy and Safety of Deep Transcranial Magnetic Stimulation for Major Depression: A Prospective Multicenter Randomized Controlled Trial. World Psychiatry. 2015;14(1):64-73. DOI · PubMed
- Dunner DL, Aaronson ST, Sackeim HA, et al. A Multisite, Naturalistic, Observational Study of Transcranial Magnetic Stimulation for Patients with Pharmacoresistant Major Depressive Disorder: Durability of Benefit Over a 1-Year Follow-Up Period. Journal of Clinical Psychiatry. 2014;75(12):1394-1401. DOI · PubMed
- Rush AJ, Trivedi MH, Wisniewski SR, et al. Acute and Longer-Term Outcomes in Depressed Outpatients Requiring One or Several Treatment Steps: A STAR*D Report. American Journal of Psychiatry. 2006;163(11):1905-1917. DOI · PubMed
- Rossi S, Antal A, Bestmann S, et al. Safety and Recommendations for TMS Use in Healthy Subjects and Patient Populations. Clinical Neurophysiology. 2021;132(1):269-306. DOI · PubMed
- McClintock SM, Reti IM, Carpenter LL, et al. Consensus Recommendations for the Clinical Application of Repetitive Transcranial Magnetic Stimulation (rTMS) in the Treatment of Depression. Journal of Clinical Psychiatry. 2018;79(1):16cs10905. DOI · PubMed