Transcranial Magnetic Stimulation Therapy: What Are The Side Effects?

Transcranial magnetic stimulation (TMS) therapy is a noninvasive treatment used to treat depression. TMS therapy uses a special coil to create magnetic fields directed at certain areas of the head. The magnetic fields created by the coil stimulate certain nerve cells associated with mood regulation in the brain to relieve symptoms of depression.

TMS therapy has been approved by the FDA as an alternative treatment to improve depressive symptoms in individuals with treatment-resistant depression (TRD), and studies have shown that TMS significantly reduces depressive symptoms in people diagnosed with TRD. But are there any side effects associated with TMS therapy?

Side Effects of TMS

At Dignity Brain Health, over 95% of patients who start TMS therapy will finish it, and it is extremely rare for someone to stop due to side effects.  Doctors using TMS therapy report minimal side effects in their patients. The few that do sometimes occur include:


Mild headaches after a treatment session are the most common side effect associated with TMS therapy. They can be caused by the stimulation of the muscles and nerves that are closest to the coil. Headaches after TMS therapy are not very common and when they happen, they are usually mild and typically resolve within days. However, TMS therapy has also been shown to reduce the duration of headaches for people who suffer from migraines.

Scalp discomfort

Scalp discomfort can occur in a small percentage of patients due to the magnetic pulses  that radiate from the coil. To protect against scalp discomfort, TMS therapy machines are equipped with sensors that regulate the temperature of the coil to avoid overheating.


Lightheadedness or dizziness is not a commonly reported side effect of TMS therapy. If it happens at all, it can occur during the procedure or after. For some people, the lightheaded feeling only lasts during the procedure, while for others it continues for a short amount of time following the procedure. In most cases, this sensation resolves quickly after the session.

Tingling and/or spasms of the facial muscles

As with headache, tingling or spasms of the facial muscles can rarely occur due to the stimulation of the nerves and muscles that are closest to the coil. This occurs in a small percentage of patients and tends to lessen throughout the course of treatment.

Rare Side Effects of TMS Therapy

More serious side effects are few and rare. However, when they do happen, they can include:


Although scary, the risk of seizure is extremely low (0.1 percent). Scientists have found that certain individuals are at a higher risk of experiencing a seizure, including people who have:

  • A history of high alcohol use or current alcohol abuse

  • A family history of seizures

  • Current sleep deprivation

  • History of a neurological condition, like stroke, brain tumor, concussions or multiple sclerosis

At Dignity Brain Health in Boston, we minimize and try and even eliminate if possible the risk of seizure by careful screening before and during your daily sessions, advising you on how to decrease your risk, and only using TMS therapy machines that have the lowest risk of seizure.

Dignity Brain Health is Here to Answer Your Questions

If you have any questions about depression, your symptoms, or any potential treatments you’ve heard of, know that you can contact our caring and attentive staff at Dignity Brain Health in Boston. We’re here to answer questions, help with treatment, and most importantly, serve as a support system for your depression treatment.