If you have tried three, four, or five antidepressants and still feel stuck, you are not failing treatment. Treatment may be failing you. Most antidepressants work by adjusting serotonin, norepinephrine, or dopamine levels in the bloodstream. But treatment-resistant depression (TRD), defined as depression that does not respond to two or more adequate medication trials, often involves underactive neural circuits that systemic medication cannot directly reach.
Transcranial magnetic stimulation (TMS) takes a different approach. Instead of flooding the brain with neurotransmitters, TMS delivers targeted magnetic pulses to specific regions involved in mood regulation. For people who have spent years cycling through SSRIs, SNRIs, and augmentation strategies, that distinction matters.
Why antidepressants stop working after years of use
About 25% of people who initially respond to an antidepressant will lose that response over time, a phenomenon called antidepressant tachyphylaxis. Sometimes described as medication “poop-out,” tachyphylaxis occurs when the brain adapts to a drug that once helped, and depressive symptoms return despite continued use at the same dose.
Research published in Innovations in Clinical Neuroscience found that among people taking fluoxetine (Prozac) who achieved full remission, 33.7% experienced a return of symptoms within 14 to 54 weeks. The response? Typically another medication trial. And then another.
The problem compounds. A 2023 reanalysis of the landmark STAR*D study, published in BMJ Open, found that the cumulative remission rate across up to four antidepressant trials was just 35% when measured by the study’s original protocol, far lower than the 67% initially reported. And by the third or fourth medication attempt, remission rates dropped to roughly 13% per step, according to the original STAR*D data – a steep decline from the 37% rate after the first trial.
Each additional SSRI or SNRI trial operates on the same basic principle: modulating monoamine neurotransmitters. When that mechanism has already failed repeatedly, trying a sixth or seventh variation of the same approach yields diminishing returns.
How TMS therapy for depression works differently
TMS bypasses the bloodstream entirely. During a session, a magnetic coil placed against the scalp delivers focused pulses to the dorsolateral prefrontal cortex, a brain region consistently shown to have reduced activity in people living with depression. These pulses create small electrical currents that activate underresponsive neurons directly.
Over multiple sessions (typically daily treatments across 4 to 6 weeks), this repeated stimulation encourages neuroplasticity: the brain’s ability to form new neural connections and strengthen existing ones. The treatment is non-invasive, requires no anesthesia or sedation, and sessions generally last 20 to 40 minutes.
The difference from antidepressants is not just one of delivery method. It is a difference of target. While SSRIs and SNRIs modify neurotransmitter availability throughout the brain and body (which is why they produce systemic side effects like weight gain, sexual dysfunction, and fatigue), TMS activates prefrontal-limbic circuits that regulate emotional processing. Think of it this way: antidepressants adjust the chemistry, while TMS reactivates the circuitry.
A 2025 consensus review backed by the National Network of Depression Centers, the Clinical TMS Society, and the International Federation of Clinical Neurophysiology confirmed TMS as an evidence-based treatment with growing applications and improving technology.
TMS success rates for treatment-resistant depression
The research here is encouraging, especially for people who have already tried multiple medications without relief.
TMS vs. switching antidepressants
A 2024 study in the American Journal of Psychiatry compared TMS head-to-head with switching to a new antidepressant in 89 people with treatment-resistant depression. The TMS group fared considerably better:
| Outcome | TMS | Antidepressant switch |
|---|---|---|
| Meaningful improvement (50%+) | 37.5% | 14.6% |
| Full remission | 27.1% | 4.9% |
| Depression score reduction | 10.02 | 4.19 |
The TMS group also reported greater improvement in anxiety and anhedonia (difficulty feeling pleasure), two symptoms that antidepressants often leave partially unresolved.
Larger studies confirm the pattern
The PCORI-funded ASCERTAIN study followed 260 adults with treatment-resistant depression across 16 health centers. Adding TMS to an existing antidepressant reduced depression severity more than switching to a different medication alone. Both TMS and adding a second medication (aripiprazole) outperformed simply switching antidepressants.
Overall response and remission rates
Across published research and a 2025 consensus review endorsed by the Clinical TMS Society, standard TMS protocols show:
- Remission rates: 30 to 36% in treatment-resistant populations
- Response rates (meaningful improvement): 40 to 58%
Newer approaches are pushing those numbers higher. The Stanford Neuromodulation Therapy (SNT) protocol, which uses brain imaging to personalize where the magnetic pulses are aimed, reported remission in up to 78.6% of participants in a controlled trial published in The American Journal of Psychiatry.
TMS for preventing relapse
A 2025 clinical trial published in JAMA Network Open found that TMS and lithium were comparably effective at preventing depression from returning. The difference: the lithium group experienced far more side effects (16 adverse events vs. 3 in the TMS group).
When to consider TMS instead of another medication switch
There is no single right moment to explore TMS, but these patterns may sound familiar:
- You have tried two or more antidepressants at adequate doses for adequate time without meaningful improvement
- A medication worked initially but stopped helping (tachyphylaxis)
- Side effects from current medications are affecting your quality of life
- Your psychiatrist keeps suggesting “one more try” with a similar class of drug
- You want a non-invasive option that does not add systemic side effects
The timeline difference also matters. A new antidepressant typically requires 6 to 8 weeks before you know whether it helps, and many people living with TRD have spent years in that cycle. TMS results often appear within 4 to 6 weeks of starting treatment, and some newer accelerated protocols condense the full course into days rather than weeks.
TMS is FDA-cleared for depression and does not require you to stop your current medications. Many people pursue TMS alongside existing prescriptions, using it as an addition rather than a replacement.
Building a complete treatment approach
TMS can be effective on its own, but outcomes may improve when combined with other evidence-based treatments. Research suggests that combining rTMS with cognitive behavioral therapy (CBT) may further improve outcomes, with some studies reporting gains of approximately 8 and 19 percentage points in response and remission rates, respectively.
For people with severe TRD who need faster relief, IV ketamine can provide improvement within hours to days rather than weeks, working through a completely different mechanism (NMDA receptor modulation) than either antidepressants or TMS. Some members begin with ketamine for acute stabilization and then transition to TMS for sustained, longer-term support.
At Nushama, our approach to treatment-resistant depression starts with a comprehensive psychiatric assessment. From there, our medical team can help identify whether TMS, ketamine therapy, Spravato (esketamine), medication management, or a combination approach fits your history and goals. Every treatment plan is individually tailored, and no one is expected to figure out the right path alone.
If you have been cycling through medications without meaningful change, a different approach may be worth exploring. Book a consultation to discuss your options with our care team.
FAQs
Does TMS work for people who have failed multiple antidepressants?
Yes. TMS was specifically FDA-cleared for treatment-resistant depression. A 2024 study in the American Journal of Psychiatry found that rTMS produced a 37.5% response rate versus just 14.6% for switching to a new antidepressant in people with moderate TRD. Standard protocols show 30 to 36% remission rates in treatment-resistant populations, and newer fMRI-guided protocols have shown higher rates in clinical trials.
How long does it take for TMS to work?
Standard TMS protocols involve daily sessions over 4 to 6 weeks. Some people notice improvement within the first 2 to 3 weeks. Newer accelerated protocols (like Stanford Neuromodulation Therapy) can compress the full course into 5 days of intensive sessions, though availability varies by clinic.
Can you do TMS and still take antidepressants?
Yes. TMS does not require stopping current medications. Many people receive TMS while continuing their existing prescriptions. The PCORI-funded ASCERTAIN study specifically evaluated adding TMS to a current antidepressant and found it more effective than switching medications.
What is the difference between TMS and ketamine for depression?
TMS and ketamine work through different mechanisms. TMS uses magnetic pulses to stimulate underactive brain regions over several weeks. IV ketamine modulates NMDA receptors and can provide relief within hours to days. For people in acute distress, ketamine may offer faster initial relief. TMS may be better suited for sustained improvement over time. Some treatment plans combine both approaches. Learn more about comparing TMS and ketamine.
Is TMS covered by insurance?
TMS is covered by many insurance plans, including Medicare, for treatment-resistant depression. Coverage typically requires documentation that you have tried at least two antidepressants without adequate response. Nushama’s care team can help verify your coverage during the consultation process.
