What is iTBS?
Intermittent theta burst stimulation (iTBS) is a patterned form of TMS that delivers bursts of pulses in a way that mimics the brain's natural theta rhythm (5 Hz). It provides the same therapeutic benefit as traditional 10 Hz TMS in a fraction of the time: typically just over 3 minutes per session instead of 19 to 37 minutes.
How iTBS works
- Burst principle: each burst has three pulses at 50 Hz, repeated at 5 Hz
- Train delivery: 2-second trains of bursts followed by 8-second rests
- Time-efficient dose: 600 pulses per session, compared with 3,000 for standard TMS
- Neuroplasticity: theta-patterned stimulation taps into the brain's learning and memory mechanisms
Evidence and FDA clearance
In 2018 the FDA cleared iTBS after the THREE-D trial, which showed it is non-inferior to 10 Hz TMS for major depressive disorder. In plain terms: at least as effective as traditional TMS, with much shorter daily visits.
iTBS compared with standard TMS
Read the transcript
What is the difference between rTMS and iTBS? rTMS is the standard TMS protocol that we use for 19 minutes. iTBS stands for intermittent theta burst stimulation.
What is theta burst stimulation? It is a triplet of pulses that the brain uses to communicate among its own circuits. That means that with theta burst stimulation, we can be more efficient in delivering brain stimulation in a shorter period of time.
To be more specific, iTBS delivers the treatment in only three minutes, while rTMS delivers the treatment in 19 minutes. According to clinical research, three minutes of iTBS is as effective in treating depression as 19 minutes of rTMS.
| Feature | iTBS | Standard 10 Hz TMS |
|---|---|---|
| Session length | About 3 minutes | 19 to 37 minutes |
| Pulses per session | 600 | 3,000 |
| FDA clearance | Yes (2018, MDD) | Yes (2008, MDD) |
| Efficacy | Non-inferior (THREE-D trial) | Established |
Session length
iTBS: About 3 minutes
Standard 10 Hz TMS: 19 to 37 minutes
Pulses per session
iTBS: 600
Standard 10 Hz TMS: 3,000
FDA clearance
iTBS: Yes (2018, MDD)
Standard 10 Hz TMS: Yes (2008, MDD)
Efficacy
iTBS: Non-inferior (THREE-D trial)
Standard 10 Hz TMS: Established
Individual results vary. Your physician tailors the protocol to your clinical profile.
How TMS protocols differ
TMS has changed a lot since the first clinical device was demonstrated in 1985 by Dr. Anthony Barker and colleagues in the UK. Today's main approaches are:
- Standard rTMS: pulses delivered through a figure-8 coil at a set frequency, typically in sessions of about 19 to 37 minutes
- Deep TMS: an H-shaped coil in a helmet, designed to reach deeper brain areas, using different settings from standard rTMS
- Theta burst (iTBS): the same coil as rTMS with patterned pulses, so a session can take about 3 minutes
- Accelerated protocols: several short sessions in one day over fewer days, which can shorten the whole course
Both standard rTMS and deep TMS are effective for depression, and iTBS has been found non-inferior to standard rTMS. Accelerated protocols are newer, and availability and coverage vary. Your doctor will recommend what fits your situation.
Who may benefit?
- Adults with major depressive disorder, including treatment-resistant depression
- Patients who want a faster, more convenient option than standard TMS
- People who have not responded to medication or had side effects
Safety and side effects
The most common effects are mild scalp discomfort, tingling or a short-lived headache early in treatment. Serious adverse effects are uncommon when protocols are followed. Not every TMS system can deliver iTBS; we use FDA-cleared systems that can.
Cost and insurance
Coverage typically applies for major depressive disorder when criteria are met. We help with documentation and prior authorization, and we verify your benefits before you start. Self-pay and financing options are available.
Frequently asked questions
Medical information on this page is educational and not a substitute for professional advice. Individual results vary.