Honest about what TMS does — and what it doesn’t.

Common & transient

• Mild headache — most common, especially in the first week. Usually resolved with over-the-counter pain relievers (Tylenol or ibuprofen).
• Scalp tingling or tenderness where the helmet sits.
• Brief facial-muscle twitching during the pulses — stops the moment the pulse stops.
• Lightheadedness for a few minutes after a session.

Most resolve within the first 1–2 weeks as the scalp acclimates.

Rare

• Seizure. The most serious risk. Rate < 0.1% in the largest sham-controlled aggregate (Tendler 2024, n = 884). This is lower than the seizure risk associated with many common antidepressants.
• Hearing changes. The machine clicks loudly, so patients wear earplugs throughout every session. With earplugs, hearing changes do not occur.
• Treatment-emergent mania. Risk < 1%; relevant primarily in bipolar spectrum. We screen and we monitor.

What TMS does not cause

• No weight gain.
• No sexual side effects.
• No memory loss. No cognitive fog.
• No sedation.
• No effect on the rest of the body — the magnetic pulse only reaches a small region of the brain.

Special populations

Pregnancy

Data are limited for the H-coil specifically. Figure-8 TMS has been used safely in pregnancy in published case series. Decisions are made carefully, with the patient and obstetric provider, balancing the risks of untreated severe depression against the limited human data on H-coil exposure. We discuss this individually.

Adolescents (15–21)

BrainsWay’s November 2025 adolescent clearance is for adjunctive use — alongside therapy and/or medication. The clearance rests on a real-world cohort of 1,120 patients, not a sham-controlled RCT in this age group. We disclose this clearly to families. Discontinuation rates in adolescents are lower than in adults (~4%); the side-effect profile is the same.

Older adults

BrainsWay’s 2024 expansion makes the H1 coil the only TMS device formally cleared for ages 22–86. Cognitive safety is documented; there is no demonstrable cognitive worsening on standardized measures. This is a meaningful contrast with ECT in the same population.

See more on the Research & Evidence library (Section on safety), or open the Frequently Asked for specific questions on memory, medications during treatment, and pregnancy.