TMS therapy's most common side effects are mild scalp discomfort and temporary headache during the first few sessions — both of which typically resolve on their own within the first week of treatment. There are no systemic side effects like those associated with antidepressant medications.
How TMS Side Effects Compare to Antidepressants
One of the most important reasons patients and providers choose TMS therapy is its favorable side-effect profile compared to antidepressant medications. Antidepressants act systemically — meaning they circulate throughout the entire body — which is why they can cause a wide range of side effects including weight gain, sexual dysfunction, sleep disruption, nausea, emotional blunting, and dry mouth.
TMS, by contrast, acts locally. The magnetic pulses stimulate a targeted region of the brain without entering the bloodstream. This means there are no systemic effects on the heart, liver, kidneys, hormones, or metabolism. For many patients — particularly those who have struggled with antidepressant side effects — this makes TMS a more tolerable and sustainable treatment option.
Learn more about how TMS compares to medication management for depression at Hamilton Psychiatric Services.
Common TMS Side Effects
The following side effects are the most frequently reported and are generally mild and temporary:
- Scalp discomfort or tingling: The most common sensation during TMS is a tapping, knocking, or tingling feeling at the site where the coil is placed on the head. This occurs because the magnetic pulses stimulate the scalp muscles as well as the underlying cortex. For most patients, this sensation becomes much less noticeable after the first few sessions as they habituate to the stimulation.
- Headache: Mild to moderate headache following a TMS session is reported by approximately 20–30% of patients, particularly during the first week of treatment. Over-the-counter pain relievers such as ibuprofen or acetaminophen are typically sufficient to manage this. Headaches almost always diminish or disappear as treatment continues.
- Lightheadedness: A small number of patients feel briefly lightheaded immediately after a session. This is transient and resolves quickly. Staying well-hydrated before and after sessions can help minimize this.
- Facial muscle twitching: Some patients notice minor twitching of facial or jaw muscles during stimulation due to the proximity of these muscle groups to the treatment area. This is normal, harmless, and stops when stimulation ends.
Importantly, there is no sedation, no anesthesia, no recovery period, and no cognitive impairment associated with TMS. Patients drive themselves to and from every session and return to work, school, or other activities immediately after.
Less Common Side Effects
A small minority of patients report the following less common effects:
- Temporary worsening of mood or anxiety: Occasional patients experience a brief period of increased anxiety or emotional sensitivity in the early weeks of treatment. This is typically transient and should be communicated to Dr. Mirza if it occurs.
- Insomnia: Rarely, patients report changes in sleep — either increased energy making it harder to fall asleep, or shifts in sleep patterns. Adjusting the timing of sessions can sometimes help.
- Ear discomfort from the clicking noise: The magnetic pulses produce a clicking sound during stimulation. Earplugs are provided during sessions and eliminate this as a concern for the vast majority of patients.
Serious Risks: Seizure
The most serious potential risk of TMS is seizure. However, this risk is extremely rare — estimated at approximately 1 in 30,000 treatment sessions in standard clinical practice. For context, the seizure risk associated with antidepressant medications (particularly bupropion at higher doses) is comparable or higher.
To minimize risk, Dr. Mirza carefully screens all patients for seizure history and other risk factors before approving TMS. Stimulation parameters are set conservatively and adjusted based on each patient's motor threshold (the level of stimulation required to produce a visible muscle response in the hand). Sessions are supervised by trained clinical staff.
Who Should Not Have TMS?
TMS is safe for the majority of adults with depression or OCD, but it is not appropriate for everyone. Patients who should not receive TMS include those with:
- Metallic implants in or near the head — including cochlear implants, deep brain stimulators, aneurysm clips, or implanted electrodes. Standard dental fillings, crowns, and braces are generally safe.
- A personal history of seizures or epilepsy — unless specifically cleared by a neurologist
- Active brain tumors or a history of stroke in the treatment area
- Certain cardiac devices — some pacemakers and implantable defibrillators may be contraindicated; Dr. Mirza will assess on a case-by-case basis
Pregnancy is not an absolute contraindication, but the evidence base for TMS during pregnancy is limited. Dr. Mirza will discuss the risk-benefit profile carefully with pregnant patients or those planning to conceive.
Frequently Asked Questions About TMS Side Effects
Does TMS cause memory loss?
No. Unlike electroconvulsive therapy (ECT), TMS does not cause memory impairment. In fact, many patients report improved cognitive clarity as their depression lifts with treatment.
Will TMS affect my ability to drive or work?
No. TMS does not cause sedation, confusion, or impaired judgment. Patients drive themselves to and from sessions and work normally throughout the treatment course.
What should I do if I get a headache after TMS?
An over-the-counter analgesic such as ibuprofen or acetaminophen is usually sufficient. Staying hydrated and resting briefly after your session can also help. If headaches are severe or persistent, notify Dr. Mirza — stimulation parameters can be adjusted.
How long do TMS side effects last?
The scalp discomfort and headaches that occur in early sessions typically improve significantly by the end of the first week and often disappear entirely by week two. Side effects do not accumulate or worsen over the treatment course for most patients.
Is TMS safe for older adults?
Yes. TMS has been studied and used safely in older adults and is generally well-tolerated. Dr. Mirza screens all patients, including older adults, for any contraindications prior to treatment.
Talk to Dr. Mirza About TMS at Hamilton Psychiatric
TMS therapy at Hamilton Psychiatric Services is delivered using the BrainsWay Deep TMS system — the most clinically validated TMS platform available — under the direct supervision of Dr. Mirza, a board-certified psychiatrist. Our clinical team monitors every session and is available to address any concerns that arise during your treatment course.
If you have questions about TMS side effects or want to find out whether TMS is right for you, we are here to help. Visit our TMS therapy page to learn more.
Call 609-631-7770 or schedule online to request a consultation at our Hamilton, NJ office.