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BDeP

13 August 2026

BDEP: Home-based transcranial direct current stimulation in bipolar depression

The BDEP study is investigating the safety and effectiveness of transcranial direct current stimulation (tDCS) for bipolar depression.

What does the study involve?

Bipolar is a prevalent and disabling disorder. The most common treatments are mood stabilising or antipsychotic medications and talking therapies. However, after a full course of treatment with antidepressant medication or psychotherapy, over one third continue to be unwell. Studies have shown that tDCS could be a possible treatment for bipolar depression.

This is a randomised, double-blind, placebo-controlled trial. There are two parts to the study. In the first part, participants are randomly allocated to either active tDCS treatment or inactive (sham) tDCS treatment for 10 weeks. The device for both the active and inactive looks the same, and neither participants nor the research team will know which has been received until the end of month 6. In the second part, everyone will be offered the active tDCS treatment.

All study visits and study activities will take place at home and participants will meet with the study team via a video call using Microsoft Teams. Participants may also choose to be seen in person at St Nicholas Hospital, Gosforth, Newcastle.

Participants will:

  • Use a tDCS headset at home.
  • Have 5 tDCS sessions per week for the first 3 weeks and then 3 sessions per week for the next 7 weeks, a total of 36 sessions during the first part of the study.
  • Attend regular study visits.
  • Complete study questionnaires.
  • Tell the study team about any changes in health or medication.

Each tDCS session lasts 30 minutes. Taking part in the study would be expected to last up to 10 months, including up to 4 weeks of screening visits.

Taking part is completely voluntary. Deciding not to take part will not affect your health care in any way, and you can stop taking part at any time without giving a reason.

What is transcranial direct current stimulation (tDCS)?

tDCS is a form of brain stimulation. It produces a small electric current (2 mA) which affects how easily brain cells can discharge. In depression, some areas of the brain that control mood do not communicate as well as they should. When brain cells can send signals more easily, these areas communicate better with each other, which may help improve mood and reduce depressive symptoms over time.

  • It does not directly stimulate brain cells to cause a seizure like electroconvulsive therapy (ECT).
  • It does not cause brain cells to discharge like transcranial magnetic stimulation (TMS).
  • The tDCS device used in this study is a headset intended for in-home use.

The study is investigating whether tDCS is effective and safe for people with bipolar depression, which is different from the type of depression for which the device is currently approved.

Who is eligible?

You may be invited to take part if some of your symptoms may be seen in bipolar depression. Participants must:

  • Be at least 18 years old.
  • Have a smart phone and internet access.

You will be asked questions about your depression symptoms and any treatments you are currently taking so that the study team can decide whether you can take part. There may be reasons why it would not be good for you to take part in the study.

What are the possible side effects?

The most common side effects are:

  • Skin redness, itching or burning sensations where the electrodes are placed on the forehead. This usually improves after the stimulation.
  • Scalp pain or neck pain.
  • Tingling, stinging or itching sensation.
  • Headache.
  • Temporary fatigue.

Less common side effects are skin irritation, increased tinnitus, small skin burns, and developing manic or hypomanic symptoms (an estimated risk of 4% with a course of active tDCS and 0.5% with inactive tDCS).

Participants will be closely monitored throughout the study, including regular mood assessments. If signs of mania occur, stimulation will be stopped and appropriate clinical support will be arranged.

Reimbursement

  • The tDCS treatment will be provided at no cost.
  • Participants will be reimbursed with a £20 voucher for each study visit attended after screening, totalling £160 if all study visits are attended.
  • Travel expenses up to £20 are available for participants who come to the research centre.
  • Participants will be able to keep the tDCS device after the study.

Interested in taking part?

Dr Niraj Ahuja, Principal Investigator
Tel: 0191 246 8606
Email: Niraj.Ahuja@cntw.nhs.uk

Rachel Sharp, Higher Research Assistant
Tel: 07970 993181
Email: Rachel.Sharp@cntw.nhs.uk

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