TMS vs. Ketamine for Depression: Which Treatment Is Right for You?

Is TMS better than ketamine for treatment-resistant depression?

Usually, there is no simple winner. Transcranial magnetic stimulation (TMS) and ketamine-based treatments are evidence-based options for treatment-resistant depression. Limited comparative evidence suggests broadly similar acute antidepressant effects, although studies differ in treatment route, protocol and design.

One pooled analysis found similar overall improvement with repetitive TMS and a single low-dose IV ketamine infusion. It was not a direct randomized head-to-head trial, however, and its IV ketamine findings should not be silently extended to intramuscular (IM) ketamine. In practice, the choice often depends on how quickly improvement is needed, medical and psychiatric history, side-effect preferences, scheduling and the likely maintenance plan.

TMS and ketamine: a practical comparison

Speed of effect TMS: Usually builds over repeated sessions. Ketamine: Can begin working within hours to days.

Durability TMS: Benefit after a successful course can persist, although relapse is possible. Ketamine: Repeated or maintenance treatment is commonly needed to sustain benefit.

Treatment frequency TMS: Commonly five days per week for several weeks; iTBS can shorten individual sessions. Ketamine: Usually involves fewer treatment days per week, with observation and recovery time.

Driving afterward TMS: Driving is usually permitted. Ketamine: Patients should not drive after treatment.

Common side effects TMS: Scalp discomfort and headache. Ketamine: Dissociation, dizziness, nausea, sleepiness and temporary blood-pressure changes.

Major screening considerations TMS: Seizure risk and metal or electronic implants in or near the head. Ketamine: Cardiovascular stability, psychotic symptoms and significant substance-use concerns.

Sedation or anaesthesia Neither treatment routinely requires anaesthesia, although temporary impairment can occur with ketamine.

How quickly do they work?

Ketamine has the faster expected onset. Antidepressant effects can emerge within hours to days, making it particularly relevant when rapid symptom reduction is clinically important. It is not a substitute for emergency care, and improvement in suicidal thoughts is not guaranteed or equivalent to preventing suicide.

TMS works differently: benefit generally accumulates across repeated treatments. Some people notice change early, while others need several weeks before the response can be assessed adequately. Different TMS protocols do not have identical schedules or evidence bases.

Which benefit lasts longer?

A successful TMS course may provide a more durable period of benefit without ongoing treatment at the same frequency. Some patients nevertheless relapse or require maintenance sessions.

The effect of a single ketamine treatment often fades, and ongoing dosing may be needed. Intranasal esketamine has maintenance evidence in people who initially respond. Evidence concerning durability varies by formulation and route; findings from IV ketamine do not establish the durability of IM racemic ketamine.

How do side effects and safety differ?

TMS is non-invasive and does not cause sedation. Patients remain awake and can generally drive afterward. Headache and scalp discomfort are the most common adverse effects. Seizure is a rare but serious risk, so clinicians screen for seizure history, relevant medications and neurological factors. Certain cranial metal or implanted electronic devices may make TMS unsuitable.

Ketamine can cause dissociation—a temporary sense of detachment or altered perception—along with dizziness, nausea, sleepiness and transient increases in blood pressure or heart rate. Monitoring and recovery time are required, and patients should arrange transportation rather than drive afterward. Cardiovascular instability, psychotic symptoms and significant substance-use concerns require careful assessment and may make treatment inappropriate.

What is the time commitment?

A standard TMS course commonly involves weekday attendance over several weeks. Intermittent theta-burst stimulation (iTBS) can make each appointment considerably shorter, but the overall schedule still requires regular attendance.

Ketamine-based treatment generally involves fewer treatment days per week, but appointments include preparation, monitoring and recovery. NeuroLinks provides IM racemic ketamine and intranasal esketamine—not IV ketamine. These options have different administration requirements and should not be treated as interchangeable.

What if the first treatment does not work?

TMS and ketamine are not mutually exclusive. An inadequate response to one does not establish that the other will fail because they differ in delivery and mechanism. The next step may involve switching treatments, revisiting the diagnosis and contributing conditions, adjusting the broader treatment plan, or considering another intervention.

Using TMS and ketamine together remains investigational. A 2023 review published in Frontiers in Neuroscience found that the evidence consisted mainly of case reports and small retrospective studies, with no established combined protocol. Combination treatment should not be assumed to work better than either treatment alone.

How do you choose?

Ketamine may be considered when speed is a major clinical priority and the patient can safely undergo monitored treatment. TMS may be attractive when avoiding medication effects, dissociation and post-treatment driving restrictions is especially important, or when a non-sedating course is preferred.

The decision requires an individualized psychiatric and medical assessment—not an online checklist. For adults on Vancouver Island or elsewhere in British Columbia, NeuroLinks can assess whether TMS, IM racemic ketamine or intranasal esketamine is a reasonable option. Contact the clinic or speak with your referring clinician to discuss next steps.