TL;DR
- •TMS and ECT are both non-pharmacological options for treatment-resistant depression — but they work very differently and serve different patient profiles.
- •TMS is non-invasive (no anesthesia, no seizure) — daily clinic visits for 4-6 weeks while you sit awake.
- •ECT involves brief electrical seizure induction under general anesthesia — 2-3 sessions per week for 3-4 weeks, then maintenance.
- •ECT has higher response rates (~60-80% in severe depression) than TMS (~40-50%) but with more side effects (memory effects, anesthesia risk).
- •For severe depression with suicidal ideation, catatonia, or psychotic features, ECT is often the right choice — works faster and more reliably.
- •Ketamine increasingly fits alongside both — faster than TMS, less burden than ECT, often the right escalation choice for moderate-to-severe TRD without severe features.
Side by side
TMS
Transcranial Magnetic Stimulation
Non-invasive neuromodulation
What it treats
Treatment-resistant major depression, OCD (specific protocols), Smoking cessation
Mechanism
Magnetic pulses through a scalp coil induce electrical currents in targeted brain regions (typically left DLPFC for depression). Awake, no anesthesia, no seizure.
Strengths
- •No anesthesia, no seizure, no cognitive side effects
- •Patient drives home after sessions
- •Outpatient — fits work/family schedules
- •No drug side effects
Limitations
- •Lower response rate than ECT (~40-50% vs 60-80%)
- •Daily clinic visits for 4-6 weeks (~30 sessions)
- •Scalp discomfort, jaw pain, mild headaches during session
- •Cost — $300-500/session, varies by insurance
- •Not effective for psychotic depression or catatonia
ECT
Electroconvulsive Therapy
Neurostimulation under anesthesia
What it treats
Severe TRD, Severe depression with psychotic features, Catatonia, Severe mania, TRD in bipolar
Mechanism
Brief electrical current induces controlled seizure under general anesthesia. Mechanism still debated — likely involves neurotrophic factor release and synaptic plasticity.
Strengths
- •Highest response rate of any depression treatment (~60-80% in severe cases)
- •Fast — response within 1-2 weeks
- •Effective for psychotic depression where most other treatments aren't
- •First-line for catatonia and severe suicidality
Limitations
- •Memory effects — short-term anterograde amnesia common; retrograde amnesia in subset
- •General anesthesia for each session
- •Can't drive on treatment days
- •Stigma + complex scheduling
- •Maintenance treatments needed to prevent relapse
Which one for your situation?
If:
Moderate-to-severe TRD, no psychotic features, no immediate safety crisis
Verdict:
TMS first — avoids ECT's side effects while still non-pharmacological
If:
Severe depression with psychotic features
Verdict:
ECT — TMS isn't effective for psychotic depression; ECT is one of the few treatments that is
If:
Catatonia (immobility, mutism, posturing)
Verdict:
ECT — first-line treatment
If:
Severe suicidality requiring rapid stabilization
Verdict:
ECT — fastest-acting; TMS too slow
If:
Multiple medication failures, cognitive impact a concern
Verdict:
TMS first; if insufficient, ECT or ketamine become next-tier
If:
Can't make daily 4-6 week clinic visits
Verdict:
ECT (2-3x weekly, fewer total visits) or ketamine (less frequent maintenance)
Where ketamine fits
Ketamine increasingly fits alongside (and sometimes before) TMS in the TRD escalation ladder. Response within hours (faster than TMS), at-home (no clinic visits), no anesthesia or memory effects. Strongest evidence in moderate-to-severe TRD without psychotic features.
TMS: 4-6 weeks of daily sessions. ECT: 1-2 weeks of 2-3x weekly. Sublingual ketamine: hours.
5-minute screening · Reviewed by a board-certified physician · FL & NJ
Frequently asked
Will I lose memories with ECT?
Memory effects are the most well-known ECT side effect. Short-term anterograde amnesia (difficulty forming new memories during treatment) is common but usually resolves weeks after treatment ends. Retrograde amnesia (forgetting past events) is less common but more concerning. Right-unilateral electrode placement significantly reduces memory effects while maintaining efficacy.
Why would I choose ECT over TMS?
When depression is severe enough that the higher response rate matters more than the side-effect cost: psychotic features, catatonia, severe suicidality requiring rapid stabilization, or TRD where TMS already failed. For moderate-to-severe TRD without those features, TMS is the preferred first-tier non-pharmacological option.
How is ketamine different?
Ketamine is pharmacological (medication) vs TMS/ECT (neurostimulation). Works through NMDA/glutamate, response within hours. TMS uses repeated magnetic stimulation over weeks. ECT induces seizures under anesthesia. All three target TRD through completely different mechanisms — patients who don't respond to one often respond to another.
Can I do TMS while on antidepressants?
Yes — most patients continue their existing antidepressants during TMS. The combination is often more effective than TMS alone, and the medication provides ongoing maintenance after the TMS course ends.
What if all three fail?
Rare but happens. Options: different ECT electrode placements or higher-frequency TMS protocols, repetitive ketamine maintenance, MAOIs (often skipped earlier due to dietary restrictions), psychedelic-assisted therapy where available, research programs. This depth of resistance warrants sub-specialist consultation rather than continued community practice.
References
- Murrough JW et al. 2013, American Journal of Psychiatry. Ketamine RCT in treatment-resistant depression — 64% response vs 28% placebo, positioning ketamine alongside TMS and ECT in the TRD escalation ladder. PMID 23982301
- Sanacora G et al. 2017, JAMA Psychiatry. APA consensus on ketamine's rapid effects relative to other treatment-resistant interventions including TMS and ECT. PMID 28249076