TMS is a noninvasive treatment that uses magnetic pulses to stimulate specific parts of the brain. Although it’s typically used to treat depression, research suggests it may be an effective treatment for bipolar disorder, too.

The Food and Drug Administration (FDA) has approved transcranial magnetic stimulation (TMS) as a treatment for major depressive disorder and, more recently, obsessive-compulsive disorder.

Depression involves symptoms that overlap with depressive episodes that occur with bipolar disorder, leading some experts to question whether TMS could be beneficial for bipolar disorder, too.

Though TMS has been used to treat depression since 1985, researchers only recently started looking at the potential benefits of TMS for bipolar disorder.

Here’s a closer look at what the research says, potential risks, and how to try TMS.

Bipolar disorder is characterized by periods of manic and depressive episodes. To date, most research around TMS for bipolar disorder has focused on its effects on depressive symptoms.

Early results are promising, suggesting TMS may reduce bipolar depressive symptoms, including:

  • lack of energy
  • feelings of hopelessness, emptiness, or sadness
  • lack of interest in activities you previously enjoyed
  • restlessness
  • feeling slower than usual
  • periods of not enough or too much sleep
  • feelings of guilt, shame, or worthlessness
  • difficulty concentrating
  • difficulty making decisions
  • suicidal ideations
  • appetite or weight fluctuations

TMS has few known side effects, which is another benefit. It may be particularly helpful if you have depressive symptoms that haven’t responded to other treatments.

In a 2019 review of clinical applications of TMS for bipolar disorder, researchers noted that the treatment significantly reduced depressive symptoms of bipolar disorder across several studies. They also looked at the effect of TMS on manic symptoms but found mixed results.

It remains unclear whether TMS offers any benefit for non-depressive symptoms.

In a small 2020 analysis of 44 people with depressive symptoms of bipolar disorder, researchers found that 77% of those who underwent TMS met their response criteria. The response criteria were defined as participants’ Montgomery-Asberg Depression Rating Scale (MADRS) depression score decreasing by at least 50%.

Among participants who completed at least 25 TMS sessions, 41% met the criteria for remission, defined as a MADRS score of less than 10. This indicates little-to-no depressive symptoms.

In a 2021 review, researchers concluded that more evidence is needed to determine the optimal technique for using TMS, including the best frequencies as well as what parts of the brain to target. For now, researchers have focused on targeting the left side of the prefrontal cortex with high frequencies.

Though the research around TMS for bipolar disorder is promising, experts still have a lot to learn about its specific benefits and how to make it as effective as possible.

What’s the FDA’s stance?

In 2020, the FDA granted TMS “breakthrough device designation” to treat bipolar disorder. This doesn’t mean the FDA has formally approved the device. But it signals there’s enough interest in the technology and evidence that it works for the FDA to accelerate a path for its formal review.

In general, TMS treatment is associated with mild side effects.

These may include:

  • mild pain or discomfort (during the procedure)
  • lightheadedness
  • mild headaches
  • insomnia
  • anxiety
  • temporary hearing difficulties
  • tingling in the face, scalp, or jaw

Very rarely, TMS has been associated with a small risk of seizures.

The U.S. Centers for Medicare and Medicaid Services notes that when used to treat depression, TMS produces clinical benefits without the systemic side effects that come with antidepressant medications.

Can TMS trigger a manic episode?

The 2019 review discussed above did find that TMS may play a part in triggering a manic switch in people experiencing depressive symptoms. More research is needed to fully understand the potential role of TMS in triggering manic symptoms.

If you’re interested in trying TMS, talk with your primary healthcare professional or psychotherapist about a referral. Although TMS is a relatively new treatment and not yet widely available, they should be able to connect you to a professional who can help.

Those who shouldn’t try TMS include:

  • those with a history of seizures or brain injuries
  • those with metal, magnetic, or implanted medical devices in their body (like a pacemaker), especially if it’s above the neckline

In the United States, the cost of TMS can range from about $230 to $334 per session, according to data from 2017. You may need 20-30 sessions a year so this cost can add up quickly. However, Medicare may reimburse TMS treatment at an average of about $206 per session. Your insurance provider may also potentially reimburse you for treatment.

You can also participate in TMS treatment by taking part in a clinical trial. If you’re interested, you can talk with your primary healthcare professional or search for local studies on ClinicalTrials.gov.

Though TMS is typically used to help treat depression, emerging research suggests it may be beneficial for managing depressive symptoms of bipolar disorder, especially those that haven’t responded to other treatments.

If you’re interested in trying TMS, talk with your care team about connecting you with a specialist or a clinical trial.