Chronic pain is a primary cause of disability and a common medical issue across the world. There are multiple treatment options for pain patients, with new treatments being developed all the time.
TMS is commonly used to treat depression, anxiety, and other mental illnesses. More recently, it’s been used to treat chronic pain. So what is TMS and how does it work? We’ll break it down together.
What is TMS Therapy?
TMS is a form of neurostimulation therapy. Neurostimulation refers to treatments that change how the nervous system reacts.
TMS stands for transcranial magnetic stimulation. It’s a type of brain stimulation using electrical pulses. The pulses create a magnetic field that stimulates the brain cells. That sounds scary but don’t worry, it’s safe and doesn’t require any surgery.
This 2020 narrative review describes TMS as: “ a safe, non-invasive technique that uses an electromagnetic coil to generate a magnetic field.”
You might also hear TMS called repetitive transcranial magnetic stimulation (rTMS) – they both refer to the same thing.
How Does TMS Therapy Work?
To understand how TMS therapy works, it’s important to understand some basics about how the brain works. The cells in your brain and nerves are known as neurons. Neurons use electrical impulses to communicate with each other and send messages to the rest of your body. TMS works to change the electrical activity inside your brain and the messages being sent.
The TMS device has either one or two coils inside it. The coils are often described as a figure of eight shape, although in some cases they might be circular. The device is placed against the patient’s head in different places to target specific areas of the brain.
When the coils are turned on they deliver magnetic impulses to the patient’s scalp. This causes a mild electrical current inside the brain.
Research shows that the electrical pulses stimulate the primary motor cortex, part of the brain responsible for controlling pain. Evidence also shows that TMS changes the way neurons in the brain interact when processing pain signals.
This 2020 review explains that the pulses: “induce alterations in the activity of cortical and subcortical brain structures that are related to pain modulation and processing”. Basically, TMS interrupts the neural connections that cause pain, providing pain relief.
You can think of it sort of like TMS helps your brain to ‘ignore’ the pain signals that are being sent by the nerves, so it doesn’t cause you to feel pain in response.
The frequency and strength of the pulses will be adjusted to suit the individual patient’s needs. Research suggests that higher frequencies produce better pain relief. Targeting different areas of the brain with the pulses can produce different results.
The therapy needs to be done regularly over a few weeks to work effectively. Usually, the patient will be given TMS for five days a week over four to six weeks. The exact schedule will be planned for each specific patient’s needs.
Who Can Have TMS Therapy?
TMS therapy might be offered if other pain treatments have failed, or even alongside other treatments for severe chronic pain.
- Chronic facial pain
- Phantom limb pain
- Back pain
- Pelvic pain
- Complex regional pain syndrome (CRPS)
- Chronic visceral pain
- Carpal tunnel syndrome
You won’t be able to have TMS therapy if you have metal in your head such as piercings that can’t be removed; a cochlear implant; shrapnel; or any other metal implants. This doesn’t include braces or fillings.
Patients who have seizures or are on medication that increases the risk of seizures may not be able to have TMS therapy. TMS can increase the risk of seizures in some cases.
What to Expect if You Have TMS Therapy
TMS is carried out at a hospital or clinic as an outpatient procedure. That means you’ll go in for the procedure and come home the same day. Usually, a doctor or technician will carry out the procedure.
You will have to remove anything metal due to the magnets used (similar to if you’re having an MRI).
You simply sit in a chair for the procedure – you’ll be awake the whole time and won’t feel any pain from the procedure. You might be given earplugs to wear as the sound of the magnetic pulses can be a bit loud.
The doctor will measure your head so they can get the size of the coil right. Once they’ve chosen the coil, they’ll put it on top of your head, usually towards the front.
When the treatment starts you might hear knocking or clicking sounds from the coil as the pulses are sent. You might also feel a light tapping sensation on your head.
Sessions tend to last between 30 and 60 minutes on average. This can vary depending on which areas of the brain are being targeted and the goals of your treatment.
Afterwards, you can go home and go back to your normal life until your next session. Since you won’t have had any sedatives or anaesthetic, you can drive and don’t need any recovery time as with some other procedures.
Potential Benefits for Chronic Pain
There are multiple potential benefits of TMS as a treatment for chronic pain. How effective TMS is will vary depending on the individual and their symptoms.
Of course, the main benefit of TMS for chronic pain patients is reducing pain levels. Research shows that TMS can be highly effective at reducing chronic pain where other treatments have failed.
A review of 33 randomised trials including 843 patients in total found that most of the studies reported: “significant pain relief after rTMS, which was frequently >30% pain reduction compared with the control treatment”.
A 2023 systematic review on TMS for fibromyalgia found that there was an improvement for participants in: “pain pressure threshold (PPT), catastrophising and quality of life when applied to the motor cortex, and in fatigue when applied to the dorsolateral prefrontal cortex.”
In some chronic pain conditions such as migraines, TMS may be able to stop the migraine in its tracks! Many migraine patients experience ‘auras’, which are warning signs that a migraine is about to begin. One study that tried providing TMS during the aura stage of migraine found that: “subjects receiving TMS were more likely to achieve pain freedom at 2 hours (39% versus 22%), and sustained pain freedom (29% versus 16%). These data suggest that the likelihood of a migraine headache is decreased if one interrupts the aura with a magnetic field.”
In some cases, TMS can provide long-lasting results, giving relief from pain for much longer than the treatment itself. This 2019 systematic review shows that the pain relief from TMS could: “last for weeks beyond the stimulation, which could be attributed to long-term synaptic plasticity, and wide-spread effects reaching remote brain areas other than the cortex” The review goes on to explain that with repeated sessions of TMS, the pain relief could even last for months.
Treating Depression and Anxiety
The American Psychiatric Association explains that: “an estimated 35% to 45% of people with chronic pain experience depression.” They go on to state that anxiety disorders are prevalent among people with chronic pain.
Mental illness can worsen chronic pain, and conversely living in pain can negatively affect your mental health.
TMS is known to help treat depression and anxiety, so it may improve the mental health of pain patients. An article from Harvard Medical School explains that: “50% to 60% of people with depression who have tried and failed to receive benefit from medications experience a clinically meaningful response with TMS.”
It may also be more cost-effective and practical for medical professionals to use TMS to treat both mental illness and chronic pain in the same sessions.
A 2021 study on TMS to treat comorbid major depressive disorder (MDD) and chronic pain found that: “both depressive and pain symptoms were significantly reduced after rTMS treatment, irrespective of age or gender.”
During TMS to treat both mental illness and chronic pain, patients may need the coil to be moved around to reach different areas of the brain.
With reduced pain levels often comes an improved ability to function. Patients may find they can get out more, be more active, and even exercise. In turn, this activity can help pain patients build strength and fitness; reduce pain levels; improve mobility; improve sleep; reduce stiffness, and even improve confidence and mental health.
In fact, evidence suggests that using both exercise and TMS may be highly effective in treating some chronic pain conditions. A 2020 study found that combining TMS with strengthening and flexibility exercises provided much greater pain relief than just exercise therapy alone.
Few Side Effects
Evidence shows that since TMS is non-invasive and doesn’t act systemically (meaning it doesn’t affect the rest of the body), it has very few side effects, unlike oral pain medications. This may make it a better option than painkillers for many pain patients.
TMS doesn’t require the use of anaesthesia or sedation, so patients can continue with their day afterwards.
Since TMS doesn’t act systemically, it can be safely used alongside many other chronic pain treatments.
Reduced Use of Pain Medication
Pain medication often has nasty side effects. Strong pain medications like opioids can have negative effects on the body. Unfortunately, opioids are also highly addictive.
If TMS can reduce pain levels, patients may be able to reduce their use of pain medication which could have positive effects on their body.
Evidence suggests that in some cases, the use of neurostimulation therapy may help patients withdraw from opioids. Research also shows that if treatments like neurostimulation are used earlier in the treatment process, it may help patients control their pain so they don’t need to start taking opioids.
Risks and Side Effects
Since TMS is non-invasive, it’s generally considered safe and doesn’t have many risks. The main risk is seizures, but this is rare. Research suggests that less than 1 in 1000 patients experience seizures as a result of TMS.
Other side effects from TMS are uncommon but may include:
- Feeling dizzy or lightheaded
- Pain in the scalp
- Neck pain
- A tingling feeling
- Facial twitching
- Feeling lethargic and drowsy
- Confusion and disorientation during treatment
- Hearing loss
Usually, side effects are mild if they do occur. Headaches and dizziness tend to pass after a few treatment sessions.
It’s important to remember that TMS won’t take chronic pain away completely and the effects won’t last forever. It also won’t ‘cure’ the root cause of your chronic pain. The treatment aims to reduce pain levels for a significant period. Efficacy will vary depending on the individual.
Although studies show promising results for TMS as a chronic pain treatment, more research is needed going forward.
Other Treatment Options
If TMS isn’t right for you, there are plenty of other chronic pain treatment options you could explore including:
- Other forms of neurostimulation: There are lots of different types of neurostimulation including other non-invasive techniques as well as invasive treatments.
- Pain medications: There are both prescription and over-the-counter pain medications which may be useful.
- Talking therapies: A range of talking therapies can help to reduce pain and help you cope with living with chronic pain. These include Cognitive Behavioural Therapy (CBT) and Acceptance and Commitment Therapy (ACT).
- Mindfulness: Mindfulness-based therapies can help you to reduce stress, which in turn can reduce pain due to the stress and pain cycle.
- Manual therapies: ‘Hands-on’ therapies like physiotherapy and massage can be useful.
- Movement therapies: Exercise-based therapies can help to reduce stiffness, improve mobility, and reduce pain levels.
- Pain management programmes: In-person or online pain management programmes like Pathways Pain Relief can help you to reduce pain levels and improve your quality of life.
Is TMS Therapy Right for You?
If you haven’t had much success with other pain treatments, or you simply think TMS sounds worth a try, it could be right for you! Many pain patients find this non-invasive treatment can help reduce their pain levels. Chat with your doctor or pain team to find out if TMS is an option for you.
- Seoyon Yang and Min Cheol Chang, (2020), “Effect of Repetitive Transcranial Magnetic Stimulation on Pain Management: A Systematic Narrative Review”. Front. Neurol., 18 February 2020, Sec. Neurorehabilitation, Volume 11 – 2020.
- Hamid P, Malik BH, Hussain ML., (2019), “Noninvasive Transcranial Magnetic Stimulation (TMS) in Chronic Refractory Pain: A Systematic Review.” Cureus. 2019 Oct 29;11(10):e6019.
- Ricardo Galhardoni PhD, Guilherme S. Correia, Haniel Araujo, et al.,(2015), “Repetitive Transcranial Magnetic Stimulation in Chronic Pain: A Review of the Literature”. Archives of Physical Medicine and Rehabilitation Volume 96, Issue 4, Supplement, April 2015, Pages S156-S172.
- Á. Conde-Antón, I. Hernando-Garijo, S. Jiménez-del-Barrio, et al., (2023), “Effects of transcranial direct current stimulation and transcranial magnetic stimulation in patients with fibromyalgia. A systematic review”. Neurología (English Edition), Volume 38, Issue 6, July–August 2023, Pages 427-439.
- Progress in Brain Research, (2021) “Transcranial Magnetic Stimulation”.
- American Psychiatric Association, (2020), “Chronic Pain and Mental Health Often Interconnected”.
- Adam P. Stern, MD, (2020), “Transcranial magnetic stimulation (TMS): Hope for stubborn depression”. Harvard Health Blog, Harvard Medical School.
- Juliana Corlier, Reza Tadayonnejad, Andrew C Wilson, et al., (2021), “Repetitive transcranial magnetic stimulation treatment of major depressive disorder and comorbid chronic pain: response rates and neurophysiologic biomarkers”. Psychological Medicine, 53(3), 823-832.
- Alejandra Cardenas-Rojas, Kevin Pacheco-Barrios, Stefano Giannoni-Luza, Oscar Rivera-Torrejon & Felipe Fregni, (2020), “Noninvasive brain stimulation combined with exercise in chronic pain: a systematic review and meta-analysis”. Expert Review of Neurotherapeutics, Volume 20, 2020 – Issue 4.
- Timothy R Deer, (2013), “Neurostimulation should be used as a method of reducing or eliminating opioids in the treatment of chronic pain: the digital drug revolution”. Expert Review of Medical Devices. Volume 10, 2013 – Issue 6.