CompletedNot ApplicableInterventional

Testing a non-invasive brain stimulation device (Nettle™) to reduce symptoms of premenstrual dysphoric disorder

Premenstrual dysphoric disorder (PMDD) is a severe health condition causing extreme mood swings, anxiety, and emotional distress in the two weeks before a period starts. This study explored whether a home-use headset called Nettle could provide relief. The Nettle device uses transcranial direct current stimulation (tDCS), which passes very weak, safe electrical currents through the scalp to support brain areas that regulate mood. In this study, 42 women tested the headset at home for 20 minutes daily between ovulation and their period, across three monthly cycles. To ensure fair results, half the participants received active stimulation while the other half received a harmless 'dummy' stimulation that felt similar. Neither the women nor the researchers knew who had the active device. The goal was to see if this non-drug treatment could safely lessen severe premenstrual symptoms.

At a glance

Status

Completed

Phase

Not Applicable

Sponsor

Queen Mary University of London

Enrolment target

Start

06 Mar 2025

Estimated completion

26 Sep 2025

Premenstrual dysphoric disorder (PMDD)

What is this study about?

Premenstrual dysphoric disorder (PMDD) is much more severe than typical premenstrual syndrome (PMS). In the week or two before their monthly bleed, people with PMDD may experience overwhelming feelings of sadness, intense anger, panic, and fatigue. These symptoms can make it very hard to work, study, or maintain relationships. While treatments like antidepressants or hormonal pills exist, they do not work for everyone and can cause unwanted side effects.

This clinical study tested a wearable home headset called Nettle. The headset uses a non-invasive technique called transcranial direct current stimulation (tDCS). It delivers tiny, painless electrical signals through pads placed on the head. Scientists believe these gentle signals help stimulate brain networks involved in managing emotions, which may help rebalance mood during the difficult second half of the menstrual cycle.

Finding non-drug, at-home treatments is vital for women's health. If proven effective, devices like Nettle could offer people with PMDD a safe, drug-free way to manage their emotional well-being in the comfort of their own homes without needing frequent hospital appointments.

Key takeaways

The study tested a gentle home-use headset (Nettle) to relieve severe PMDD mood symptoms.
It involved 42 women using the headset for 20 minutes daily across three menstrual cycles.
Half of the participants received active stimulation, while half received a harmless dummy treatment.
The treatment is drug-free, non-invasive, and completed entirely at home.
Participants tracked their daily moods through simple questionnaires to measure symptom changes.

Who may be eligible?

This study was open to women and individuals assigned female at birth aged between 18 and 45 who have regular menstrual periods. Participants needed to either have an official diagnosis of PMDD or experience severe monthly emotional symptoms that fit the condition.

To ensure results were clear and safe, certain people could not join. Anyone who was pregnant, had a neurological condition (such as epilepsy), or used tobacco, nicotine products, or recreational drugs was excluded. Drinking more than 14 units of alcohol per week also meant a person could not take part.

Additionally, volunteers could not be taking antidepressants or hormonal treatments (such as hormonal contraceptives for PMDD or other mental health conditions). This was to make sure any improvements could be linked directly to the headset rather than medicines.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you aged between 18 and 45?
Were you assigned female at birth and do you have regular periods?
Do you experience severe mood swings, depression, or anxiety in the two weeks before your period?
Are you free from neurological conditions (like epilepsy) and not pregnant?
Are you currently not taking antidepressants or hormonal treatments for PMDD?
Do you drink fewer than 14 units of alcohol a week and avoid smoking or nicotine?

Answer every question to see your result.

What does participation involve?

Taking part in the study took place entirely from home over three full menstrual cycles (around three months). Participants were provided with the Nettle headset and given clear instructions on how to use it safely. Each month, starting the day after estimated ovulation and finishing the day before their period began, participants wore the headset for 20 minutes a day.

Volunteers were randomly placed into one of two groups: one received active brain stimulation, and the other received 'sham' (dummy) stimulation, which felt similar but did not deliver active currents. Participants completed brief daily symptom diaries on their phones or computers, along with detailed questionnaires at the start, middle, and end of the trial to track changes in mood, anxiety, and daily living.

Potential risks and benefits

Participants using the active headset had the chance of experiencing reduced PMDD symptoms, although improvement could not be guaranteed. Taking part also helped advance scientific understanding of PMDD treatments. The stimulation is non-invasive and generally considered very safe, but minor side effects can include temporary skin redness, mild itching, or a light tingling feeling under the headset pads. Taking part was entirely voluntary, and participants were free to withdraw from the study at any time without their usual NHS care being affected.

Locations (1)

Queen Mary University of London
Approximate
London, England

Common questions

Does the brain stimulation hurt?

No. The stimulation uses tiny electrical currents that are non-invasive. Most people only feel a mild tingling, warmth, or itching sensation on the scalp when the device is turned on.

What is a 'sham' device?

A sham device is a dummy treatment. It looks and feels like the real headset and gives a brief tingling sensation at the start, but it does not provide continuous stimulation. This helps researchers test if the real treatment truly works.

Did participants have to go into a hospital?

No. The trial was designed for convenience, allowing participants to use the headset at home while keeping in touch with the study team remotely.

Why were people taking antidepressants excluded?

Antidepressants alter brain chemistry and mood. To know for certain whether the headset alone works, researchers needed participants who were not currently using mood-altering medications.

Who ran and funded this study?

The study was conducted by researchers at Queen Mary University of London and funded by the Small Business Research Initiative for Healthcare (SBRI) and university research funds.

How to find out more

Paul Faulkner

p.faulkner@qmul.ac.uk +44 (0)7949069012 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.