What Is TMS (Transcranial Magnetic Stimulation)

This page reflects our understanding of mental health topics as of 2026. If you are reading this at a later date, some details may no longer be current, so please verify anything important against up to date sources. If you notice anything that needs updating, we would welcome you letting us know.

Transcranial magnetic stimulation (TMS) is a non-invasive treatment that uses magnetic pulses to stimulate specific areas of the brain involved in mood. It is approved by Health Canada for treating depression and is most often offered to people whose depression has not improved enough with antidepressant medication. During a session, a magnetic coil is placed against the scalp while the person is awake and seated. No anesthesia is needed, and people can usually return to normal activities right afterward. Treatment typically involves sessions five days a week for four to six weeks. Canadian clinical guidelines recognize repetitive TMS as an effective option for depression after at least one medication has not helped.

How TMS Works

In depression, certain brain regions, particularly an area in the front of the brain involved in mood regulation, may be less active. TMS uses a magnetic field to create small electrical currents in that area, which over repeated sessions appear to strengthen activity in mood-related brain networks. The magnetic field passes through the skull without surgery or implants.

What Treatment Involves

1. Assessment. A psychiatrist or physician confirms that TMS is appropriate, reviews medical history, and checks for factors that increase risk.
2. Mapping. At the first session, the team finds the right position and strength for the pulses.
3. Treatment sessions. You sit in a chair while the coil delivers pulses, which feel like tapping on the scalp. Standard sessions last about 20 to 40 minutes, and a newer form called theta burst stimulation can take only a few minutes.
4. Course of treatment. Sessions usually happen on weekdays for four to six weeks, followed by a review of progress.

Who May Benefit

TMS is mainly used for major depression that has not responded well to one or more antidepressants, or for people who cannot tolerate medication side effects. It is being studied and used for other conditions, such as OCD, and research is ongoing. It is usually combined with continued therapy, medication, or both, as described on the page about treatment-resistant depression.

Questions to Ask Before Starting TMS

If you are considering TMS, it can help to ask the treating team questions such as: What type of TMS do you offer, and how long is each session? How many sessions are typical? How will progress be measured? What happens if symptoms return after treatment? Can I continue my current medication and therapy? What are the costs, and is any coverage available? Clear answers help you plan around the time commitment and make an informed decision alongside your physician or psychiatrist.

Side Effects and Safety

The most common side effects are scalp discomfort and headaches, which usually ease over the course of treatment. Seizures are a rare but serious risk, so people with certain medical conditions or metal implants in or near the head may not be suitable candidates. Unlike electroconvulsive therapy, TMS does not require anesthesia and does not typically affect memory.

Access in BC

TMS is offered through some publicly funded hospital programs and private clinics. Public programs may have referral requirements and waitlists, while private clinics usually charge fees, and coverage varies. A psychiatrist or family doctor can help you explore whether TMS is an option and how to access it.

What It Is Not

TMS is not electroconvulsive therapy, and it is not a quick fix. Improvements usually develop over several weeks, and not everyone responds. It also does not replace other parts of care. Therapy remains important for building coping skills and preventing relapse, as described on the page about how depression is treated.

Getting Support at Pacific Maple Psych Centre

If you are exploring options for depression or other concerns, talking with a clinician can help you weigh which approaches fit your situation, both those widely available now and newer treatments as they become more accessible.