Quick answer
Most adults with major depression or OCD who haven’t found relief from an antidepressant, or who couldn’t tolerate one long enough to know, may wish to consider screening for TMS.
A short list of physical factors can rule someone out; mainly certain metal implants, a seizure history, or taking specific medications. We’ll go through all this in the complimentary pre-screening.
Introduction
Here’s what goes into the eligibility decision at Compassion Neurohealth, from considering the clinical picture of who TMS helps to the checklist of things that can rule someone out.
Key takeaways:
- Candidacy typically starts with a diagnosis of major depression or OCD, confirmed by a clinician.
- Not responding to oral medication, or not being able to tolerate it, both count toward eligibility.
- A small number of physical factors can rule someone out, like certain metal implants or seizure history.
- Other possibly temporary situations, like a past head injury or pregnancy, call for individual review rather than automatic exclusion.
- The only way to know for certain is a candidacy evaluation.
The clinical picture of a likely candidate
Most suitable candidates for TMS have a confirmed diagnosis of a condition like OCD or major depression, a documented history of medication, and no red flags on the safety screen.
Diagnosis before TMS Treatment
TMS is FDA-cleared for major depressive disorder and OCD. That diagnosis needs to come from a clinical evaluation, not a self-assessment or an online quiz.
If you haven’t had a formal psychiatric evaluation, that’s usually the first step, and Compassion Neurohealth can help arrange one. We also accept referrals from healthcare providers following on from a relevant diagnosis.
Prior treatment history
The minimum regulatory requirement before seeking TMS is to have tried at least one antidepressant without adequate relief, but some insurance policies require more than one medication to have been tried. Your evaluation will explore which medications you tried, at what dose, for how long, and why you stopped each one.
Medication intolerance as a pathway to TMS
The effects of each medication you have tried will be considered in full, as well as whether the side effects compelled you to stop before it had a fair chance to work. Either experience likely means you haven’t been able to complete effective medication treatment, which is key to TMS eligibility.
You may also meet this criterion by not having responded to medication in a clinical trial, or having to leave because of side effects.
Why “treatment-resistant” is a description, not a judgment
“Treatment-resistant depression” is a clinical term. It describes how much prior treatment someone has tried, nothing about effort, willpower, or how hard someone fought their symptoms.
This term is used for insurance documentation and treatment planning. It says nothing about whether your depression is permanent, and it is not a comment on how you have been approaching getting well.
How many medications you need to have tried
No single number applies everywhere, and that inconsistency often causes confusion.
Why sources disagree
FDA clearance for TMS sets a floor of one prior antidepressant without adequate response. Insurance medical necessity criteria sit above that floor and vary by company, often asking for two to four documented trials.
Individual clinics may set their own program criteria on top of both. That’s why the number you find on one website won’t always match another.
What counts as an adequate medication trial
An adequate trial generally means taking a therapeutic dose, as prescribed, for long enough to know whether it worked. This is often around six to eight weeks.
A medication stopped after a few days because of side effects doesn’t count the same way toward that number, even though it still supports candidacy through the intolerance pathway above.
What may rule you out for TMS?
A short list of physical factors aren’t TMS-compatible. Your initial evaluation screens for all of them.
Ferromagnetic material in the head or neck
Aneurysm clips or coils, metal fragments, or other ferromagnetic material near the treatment area pose a real physical risk under a strong magnetic field. Dental fillings and braces are a separate matter and don’t rule someone out.
Implanted devices
Pacemakers, implantable cardioverter-defibrillators, deep brain stimulators, vagus nerve stimulators, cochlear implants, and implanted medication pumps all carry a risk of interference or malfunction near the TMS coil.
Seizure or epilepsy history
TMS carries a small risk of inducing a seizure, and that risk rises for people with a personal history of seizures or epilepsy. Your evaluation asks about this in detail, including how long ago and under what circumstances.
Medications that lower seizure threshold
Some medications raise seizure risk on their own, including high doses of certain antidepressants, tramadol, and some antipsychotics or stimulant combinations. Your full medication list gets reviewed before treatment starts, not just your psychiatric medications.
Why some of these are absolute, and others are a clinical conversation
Ferromagnetic implants and cardiac or neurological devices carry a direct physical hazard, which makes them close to non-negotiable.
A distant seizure history or a single medication that mildly lowers seizure threshold is often a different kind of decision. Your prescribing physician weighs the specifics with you rather than applying a blanket rule.
Situations that need individual evaluation
None of these automatically rule someone out, but all of them call for a closer look before your care team gives you an answer.
Prior head injury
Structural changes from a past head injury can affect coil placement or add a layer of caution to planning. Most people with a head injury history are still evaluated individually rather than excluded outright.
Bipolar depression
TMS is used for bipolar depression in clinical practice. The main concern is the small possibility of triggering a manic episode, so your evaluation looks closely at your current mood stabilizer regimen and mood history.
Pregnancy and breastfeeding
TMS doesn’t circulate medication through your body, which is part of why some clinicians see it as worth discussing for patients who want to limit drug exposure during pregnancy or while breastfeeding. Safety data here is more limited than for antidepressants, so this decision gets coordinated between your psychiatric provider and your OB.
Adolescents
In 2026, TMS received FDA clearance as an adjunctive treatment for major depressive disorder (MDD) in adolescents aged 15–21 years.
Some clinics may consider TMS for adolescents off-label for other conditions, with parental consent and in collaboration with a wider care team.
What happens at a candidacy evaluation
Your evaluation covers three things:
- Symptom scales, like the PHQ-9, to establish a baseline and confirm the diagnosis fits.
- Treatment history review, covering every medication or therapy you’ve tried and why each one stopped.
- Contraindication screening, covering implants, metal, seizure history, and your current medication list.
Most of this happens through conversation and a short set of screening questions.
If you are not a candidate right now
“Not right now” does not mean “never”. A device scheduled for removal, a pregnancy that will end, or a temporary course of a seizure-threshold-lowering medication may mean TMS is a future possibility.
Your care team can talk through interim options and revisit your candidacy once your situation changes.
Find Out If You Are a Candidate
Reading about candidacy criteria only goes so far. The clearest answer comes from a short conversation with someone trained to screen for it.
Compassion Neurohealth offers a complimentary pre-screening to review your history and answer your questions directly, with no commitment to start treatment.
Frequently asked questions
Q: How Many Antidepressants Do I Need to Have Tried?
A: FDA clearance sets a floor of one prior antidepressant trial without adequate relief, while most insurance plans ask for two to four documented trials. Your evaluation will confirm what applies to your specific situation and coverage.
Q: Can I Have TMS if I Have Metal in My Head or an Implanted Device?
A: It depends on what kind. Dental fillings and braces don’t rule you out. Ferromagnetic material like aneurysm clips and devices like pacemakers, defibrillators, or deep brain stimulators typically do. Your screening will ask about the specific type and location of any metal or device.
Q: Can Teenagers Have TMS?
A: Current FDA clearance for TMS covers adults primarily, and TMS as an adjuvant treatment for adolescents aged 15-12 years for major depressive disorder. Some clinics offer TMS to adolescents off-label under specific protocols with parental involvement, decided on a case-by-case basis. Ask your evaluation team directly about age-specific criteria.
Q: Do I Need a Referral From My Psychiatrist?
A: Not to schedule an evaluation. Many people self-refer, and Compassion Neurohealth coordinates directly with your existing psychiatrist or therapist for records and ongoing care. A referral can still help speed up insurance authorization.
Q: Can I Keep Taking My Medication During TMS?
A: Yes, in most cases. TMS is typically added alongside your current medication rather than replacing it. Your full medication list gets reviewed during screening, since a small number of medications affect seizure risk and factor into your treatment plan.
Q: Can I Have TMS if I Have Had a Head Injury?
A: Often, yes, though it depends on the specifics of the injury. A past head injury calls for individual review rather than automatic exclusion, since structural changes can affect coil placement and treatment planning.
Q: Can I Have TMS While Pregnant or Breastfeeding?
A: This is decided individually, coordinated between your psychiatric provider and your OB. TMS doesn’t circulate medication through the body, which is part of why some providers see it as worth discussing during pregnancy or breastfeeding, though safety data is more limited than for antidepressants.
