Irritable Bowel Syndrome (IBS-C)NCT07662083
Trans Auricular Vagal Nerve Stimulation in Patients With IBS-C
A study testing Transcutaneous Auricular Vagus Nerve Stimulation (ta-VNS) in people with Irritable Bowel Syndrome (IBS-C), run by West Virginia University at 1 site in United States.
Trial summary
This study evaluates the efficacy and safety of transcutaneous auricular vagus nerve stimulation (ta-VNS) in adults with constipation-predominant irritable bowel syndrome (IBS-C). Participants will be randomized to receive either active or sham stimulation using a non-invasive auricular device over a 60-day period. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Irritable Bowel Syndrome (IBS-C)
- What is being tested?
- Transcutaneous Auricular Vagus Nerve Stimulation (ta-VNS)
- Type of treatment
- Medical device
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 80 participants
- Where
- 1 siteUnited States
- Study dates
- Jul 2026to Jul 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Referred to the WVU Department of Gastroenterology and Hepatology
- Diagnosis of IBS-C
Who cannot join
- Failure of second-line therapy with secretagogues (linaclotide, lubiprostone, plecanatide, or tenapanor)
- Failure of third-line therapy with tegaserod
- Known debilitating psychiatric illness
- Cognitive impairment
- Pregnancy
- Prisoners
Show all 11Show fewer
- Active substance use disorder
- Concurrent opioid use
- History of major gastrointestinal surgery resulting in luminal alteration
- History of vagotomy
- Secondary causes of constipation (e.g., opioid use, uncontrolled hypothyroidism, celiac disease)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site
West Virginia University- Gastroenterology and Hepatology
Morgantown, West Virginia, 26506
Zain Sobani, MD, 304-598-6200, zain.sobani@hsc.wvu.edu
Zain Sobani, MD
About this study
Official title: Randomized Controlled Trial Evaluating Trans Auricular Vagal Nerve Stimulation in Patients With Irritable Bowel Syndrome Constipation Subtype
This study evaluates the efficacy and safety of transcutaneous auricular vagus nerve stimulation (ta-VNS) in adults with constipation-predominant irritable bowel syndrome (IBS-C). Participants will be randomized to receive either active or sham stimulation using a non-invasive auricular device over a 60-day period.
The primary objectives are to assess changes in symptom severity and quality of life using validated instruments, including the IBS Symptom Severity Scale (IBS-SSS) and the IBS Quality of Life questionnaire (IBS-QOL). Secondary assessments include safety and participant compliance.
This study aims to determine whether ta-VNS is an effective non-invasive therapeutic modality for improving symptoms and quality of life in patients with IBS-C.
- Conditions
- Irritable Bowel Syndrome (IBS-C)
- Being tested
- Transcutaneous Auricular Vagus Nerve Stimulation (ta-VNS), Sham Transcutaneous Auricular Vagus Nerve Stimulation
- Keywords
- Trans Auricular Vagal Nerve Stimulation
- Medical subject headings
- Irritable Bowel Syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Transcutaneous Auricular Vagus Nerve Stimulation (ta-VNS)Device
Delivery of non-invasive electrical stimulation to the auricular branch of the vagus nerve using the Parasym device. Stimulation is applied via an ear clip at 25 Hz and 250 microseconds, with intensity titrated to just below discomfort (0-36 mA). Administered for 30 minutes daily over 60 days.
Sham Transcutaneous Auricular Vagus Nerve StimulationDevice
Use of a sham Parasym device that mimics active stimulation but delivers only a brief, low-level output at session onset before ramping down to zero for the remainder of the 30-minute session. Administered daily for 60 days to maintain participant blinding.
| Study group | Role | What they receive |
|---|---|---|
| Transcutaneous Auricular Vagus Nerve Stimulation (ta-VNS) | Experimental | Participants will receive active transcutaneous auricular vagus nerve stimulation (ta-VNS) using the Parasym device (Parasym Health, Inc., London, UK). The device delivers electrical stimulation to the auricular branch of the vagus nerve via an ear clip. Stimulation will be administered once daily for 30 minutes over 60 days at a consistent time chosen by the participant. Stimulation parameters are set at 25 Hz and 250 microseconds, with intensity adjusted to just below the participant's discomfort threshold (0-36 mA). Receives: Device: Transcutaneous Auricular Vagus Nerve Stimulation (ta-VNS) |
| Sham Transcutaneous Auricular Vagus Nerve Stimulation | Sham comparator | Participants will receive sham stimulation using an identical-appearing Parasym device. The device delivers a brief, low-level electrical output at the start of each session, which ramps down to zero and provides no stimulation for the remainder of the session. Sessions will last 30 minutes daily for 60 days at a consistent time of the participant's choosing. The device will look, feel, and sound identical to the active device to maintain blinding. Receives: Device: Sham Transcutaneous Auricular Vagus Nerve Stimulation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change From Baseline in IBS Symptom Severity Scale (IBS-SSS) Score at Day 60
Evaluate the effect of transcutaneous auricular vagus nerve stimulation (ta-VNS) on symptom severity in patients with IBS-C using the IBS Symptom Severity Scale (IBS-SSS). The IBS-SSS assesses abdominal pain severity and frequency, abdominal distension, bowel habit satisfaction, and interference with quality of life. Scores range from 0 to 500, with higher scores indicating more severe symptoms (≤75 remission, 75-174 mild, 175-299 moderate, 300-500 severe). The outcome measure is defined as the change in IBS-SSS score from baseline to Day 60.
Measured: Baseline to Day 60
Change From Baseline in IBS Quality of Life (IBS-QOL) Total Score at Day 60
Evaluate the impact of ta-VNS on quality of life in patients with IBS-C using the IBS Quality of Life (IBS-QOL) questionnaire. The IBS-QOL is a 34-item validated instrument scored on a 5-point Likert scale and converted into a total score ranging from 0 to 100, with higher scores indicating better quality of life. The outcome measure is defined as the change in IBS-QOL total score from baseline to Day 60.
Measured: Baseline to Day 60
Secondary outcomes (3)
Incidence of Adverse Events
Evaluate the safety of ta-VNS in patients with IBS-C by assessing the incidence of adverse events during the 60-day intervention period.
Measured: Baseline through Day 60
Participant Compliance With ta-VNS Intervention
Assess participant compliance with the ta-VNS intervention by measuring the number of days the device was used according to the study protocol over the 60-day intervention period.
Measured: Baseline to Day 60
Change From Baseline in IBS Quality of Life (IBS-QOL) Domain Scores at Day 60
Evaluate the impact of transcutaneous auricular vagus nerve stimulation (ta-VNS) in patients with IBS-C using the IBS Quality of Life (IBS-QOL) questionnaire domain scores. The IBS-QOL is a validated instrument that includes the following domains: dysphoria, interference with activity, body image, health worry, food avoidance, social reaction, and relationships. Each domain score is transformed to a 0 to 100 scale, with higher scores indicating better quality of life. The outcome measure is defined as the change in each domain score from baseline to Day 60.
Measured: Baseline to Day 60
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Jun 2026
- Study startJul 2026 (estimated)
- Primary completionMay 2027 (estimated)
- Study completionJul 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (7)Papers the sponsor has linked to this study.
- Other trials for Irritable Bowel Syndrome (IBS-C)Studies of the same condition, open and under way.
- More trials run by West Virginia UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind
- Who is masked
- Participant, Care provider, Outcomes assessor
- Enrolment
- 80 participants (estimated)
Sponsor and investigators
- Lead sponsor
- West Virginia University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Zain Sobani, West Virginia University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07662083
- Sponsor's protocol ID
- STUDY00000105
- Status last verified
- Jun 2026
- First submitted
- 17 Jun 2026
- Last updated
- 23 Jun 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- No
Publications
Hou L, Rong P, Yang Y, Fang J, Wang J, Wang Y, Zhang J, Zhang S, Zhang Z, Chen JDZ, Wei W. Auricular Vagus Nerve Stimulation Improves Visceral Hypersensitivity and Gastric Motility and Depression-like Behaviors via Vago-Vagal Pathway in a Rat Model of Functional Dyspepsia. Brain Sci. 2023 Feb 1;13(2):253. doi: 10.3390/brainsci13020253.
PubMed 36831796Zhu Y, Xu F, Sun C, Xu W, Li M, Gong Y, Rong P, Lin L, Chen JDZ. Noninvasive Transcutaneous Auricular Vagal Nerve Stimulation Improves Gastric Slow Waves Impaired by Cold Stress in Healthy Subjects. Neuromodulation. 2023 Dec;26(8):1851-1857. doi: 10.1016/j.neurom.2022.03.010. Epub 2022 May 19.
PubMed 35597733Liu J, Lv C, Yin M, Zhu M, Wang B, Tian J, Hashimoto K, Yu Y. Efficacy and Safety of Transcutaneous Auricular Vagus Nerve Stimulation in Patients With Constipation-Predominant Irritable Bowel Syndrome: A Single-Center, Single-Blind, Randomized Controlled Trial. Am J Gastroenterol. 2024 Dec 17;120(9):2139-2153. doi: 10.14309/ajg.0000000000003257.
PubMed 39689011Weronika Górska and Mikołaj Raszek, Auricular versus Cervical Vagus Nerve Stimulation: A Narrative Perspective on Safety, Mechanisms, and Clinical Applicability. MAR Neurology, Neurosurgery & Psychology, 2025. 9(4).
Shi X, Hu Y, Zhang B, Li W, Chen JD, Liu F. Ameliorating effects and mechanisms of transcutaneous auricular vagal nerve stimulation on abdominal pain and constipation. JCI Insight. 2021 Jul 22;6(14):e150052. doi: 10.1172/jci.insight.150052.
PubMed 34138761Kovacic K, Hainsworth K, Sood M, Chelimsky G, Unteutsch R, Nugent M, Simpson P, Miranda A. Neurostimulation for abdominal pain-related functional gastrointestinal disorders in adolescents: a randomised, double-blind, sham-controlled trial. Lancet Gastroenterol Hepatol. 2017 Oct;2(10):727-737. doi: 10.1016/S2468-1253(17)30253-4. Epub 2017 Aug 18.
PubMed 28826627Almario CV, Sharabi E, Chey WD, Lauzon M, Higgins CS, Spiegel BMR. Prevalence and Burden of Illness of Rome IV Irritable Bowel Syndrome in the United States: Results From a Nationwide Cross-Sectional Study. Gastroenterology. 2023 Dec;165(6):1475-1487. doi: 10.1053/j.gastro.2023.08.010. Epub 2023 Aug 16.
PubMed 37595647
Study at a glance
From the registry record, last updated by the sponsor on 23 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Randomized Controlled Trial Evaluating Trans Auricular Vagal Nerve Stimulation in Patients With Irritable Bowel Syndrome Constipation Subtype
- ClinicalTrials.gov ID
- NCT07662083
- Acronym / sponsor ID
- STUDY00000105
- Conditions
- Irritable Bowel Syndrome (IBS-C)
- Keywords
- Trans Auricular Vagal Nerve Stimulation
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 80 participants (estimated)
- Lead sponsor
- West Virginia UniversityUniversity, hospital or other
- Study start
- Jul 2026 (estimated)
- Primary completion
- May 2027 (estimated)
- Study completion
- Jul 2027 (estimated)
- First posted
- 23 Jun 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study evaluates the efficacy and safety of transcutaneous auricular vagus nerve stimulation (ta-VNS) in adults with constipation-predominant irritable bowel syndrome (IBS-C). Participants will be randomized to receive either active or sham stimulation using a non-invasive auricular device over a 60-day period.
The primary objectives are to assess changes in symptom severity and quality of life using validated instruments, including the IBS Symptom Severity Scale (IBS-SSS) and the IBS Quality of Life questionnaire (IBS-QOL). Secondary assessments include safety and participant compliance.
This study aims to determine whether ta-VNS is an effective non-invasive therapeutic modality for improving symptoms and quality of life in patients with IBS-C.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, care provider, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Transcutaneous Auricular Vagus Nerve Stimulation (ta-VNS) | Experimental | Device: Transcutaneous Auricular Vagus Nerve Stimulation (ta-VNS)Participants will receive active transcutaneous auricular vagus nerve stimulation (ta-VNS) using the Parasym device (Parasym Health, Inc., London, UK). The device delivers electrical stimulation to the auricular branch of the vagus nerve via an ear clip. Stimulation will be administered once daily for 30 minutes over 60 days at a consistent time chosen by the participant. Stimulation parameters are set at 25 Hz and 250 microseconds, with intensity adjusted to just below the participant's discomfort threshold (0-36 mA). |
| Sham Transcutaneous Auricular Vagus Nerve Stimulation | Sham comparator | Device: Sham Transcutaneous Auricular Vagus Nerve StimulationParticipants will receive sham stimulation using an identical-appearing Parasym device. The device delivers a brief, low-level electrical output at the start of each session, which ramps down to zero and provides no stimulation for the remainder of the session. Sessions will last 30 minutes daily for 60 days at a consistent time of the participant's choosing. The device will look, feel, and sound identical to the active device to maintain blinding. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Referred to the WVU Department of Gastroenterology and Hepatology
- Diagnosis of IBS-C
Key exclusion criteria (11 listed)
- Failure of second-line therapy with secretagogues (linaclotide, lubiprostone, plecanatide, or tenapanor)
- Failure of third-line therapy with tegaserod
- Known debilitating psychiatric illness
- Cognitive impairment
- Pregnancy
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Transcutaneous Auricular Vagus Nerve Stimulation (ta-VNS)Delivery of non-invasive electrical stimulation to the auricular branch of the vagus nerve using the Parasym device. Stimulation is applied via an ear clip at 25 Hz and 250 microseconds, with intensity titrated to just below discomfort (0-36 mA). Administered for 30 minutes daily over 60 days. | Device | Transcutaneous Auricular Vagus Nerve Stimulation (ta-VNS) |
| Sham Transcutaneous Auricular Vagus Nerve StimulationUse of a sham Parasym device that mimics active stimulation but delivers only a brief, low-level output at session onset before ramping down to zero for the remainder of the 30-minute session. Administered daily for 60 days to maintain participant blinding. | Device | Sham Transcutaneous Auricular Vagus Nerve Stimulation |
Primary outcome
Change From Baseline in IBS Symptom Severity Scale (IBS-SSS) Score at Day 60
Time frame: Baseline to Day 60
Evaluate the effect of transcutaneous auricular vagus nerve stimulation (ta-VNS) on symptom severity in patients with IBS-C using the IBS Symptom Severity Scale (IBS-SSS). The IBS-SSS assesses abdominal pain severity and frequency, abdominal distension, bowel habit satisfaction, and interference with quality of life. Scores range from 0 to 500, with higher scores indicating more severe symptoms (≤75 remission, 75-174 mild, 175-299 moderate, 300-500 severe). The outcome measure is defined as the change in IBS-SSS score from baseline to Day 60.
Change From Baseline in IBS Quality of Life (IBS-QOL) Total Score at Day 60
Time frame: Baseline to Day 60
Evaluate the impact of ta-VNS on quality of life in patients with IBS-C using the IBS Quality of Life (IBS-QOL) questionnaire. The IBS-QOL is a 34-item validated instrument scored on a 5-point Likert scale and converted into a total score ranging from 0 to 100, with higher scores indicating better quality of life. The outcome measure is defined as the change in IBS-QOL total score from baseline to Day 60.
3 secondary outcomes
Incidence of Adverse Events
Time frame: Baseline through Day 60
Participant Compliance With ta-VNS Intervention
Time frame: Baseline to Day 60
Change From Baseline in IBS Quality of Life (IBS-QOL) Domain Scores at Day 60
Time frame: Baseline to Day 60
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 Jun 2026.
- Background: PubMed 36831796Hou L, Rong P, Yang Y, Fang J, Wang J, Wang Y, Zhang J, Zhang S, Zhang Z, Chen JDZ, Wei W. Auricular Vagus Nerve Stimulation Improves Visceral Hypersensitivity and Gastric Motility and Depression-like Behaviors via Vago-Vagal Pathway in a Rat Model of Functional Dyspepsia. Brain Sci. 2023 Feb 1;13(2):253. doi: 10.3390/brainsci13020253.
- Background: PubMed 35597733Zhu Y, Xu F, Sun C, Xu W, Li M, Gong Y, Rong P, Lin L, Chen JDZ. Noninvasive Transcutaneous Auricular Vagal Nerve Stimulation Improves Gastric Slow Waves Impaired by Cold Stress in Healthy Subjects. Neuromodulation. 2023 Dec;26(8):1851-1857. doi: 10.1016/j.neurom.2022.03.010. Epub 2022 May 19.
- Background: PubMed 39689011Liu J, Lv C, Yin M, Zhu M, Wang B, Tian J, Hashimoto K, Yu Y. Efficacy and Safety of Transcutaneous Auricular Vagus Nerve Stimulation in Patients With Constipation-Predominant Irritable Bowel Syndrome: A Single-Center, Single-Blind, Randomized Controlled Trial. Am J Gastroenterol. 2024 Dec 17;120(9):2139-2153. doi: 10.14309/ajg.0000000000003257.
- BackgroundWeronika Górska and Mikołaj Raszek, Auricular versus Cervical Vagus Nerve Stimulation: A Narrative Perspective on Safety, Mechanisms, and Clinical Applicability. MAR Neurology, Neurosurgery & Psychology, 2025. 9(4).
- Background: PubMed 34138761Shi X, Hu Y, Zhang B, Li W, Chen JD, Liu F. Ameliorating effects and mechanisms of transcutaneous auricular vagal nerve stimulation on abdominal pain and constipation. JCI Insight. 2021 Jul 22;6(14):e150052. doi: 10.1172/jci.insight.150052.
- Background: PubMed 28826627Kovacic K, Hainsworth K, Sood M, Chelimsky G, Unteutsch R, Nugent M, Simpson P, Miranda A. Neurostimulation for abdominal pain-related functional gastrointestinal disorders in adolescents: a randomised, double-blind, sham-controlled trial. Lancet Gastroenterol Hepatol. 2017 Oct;2(10):727-737. doi: 10.1016/S2468-1253(17)30253-4. Epub 2017 Aug 18.
- Background: PubMed 37595647Almario CV, Sharabi E, Chey WD, Lauzon M, Higgins CS, Spiegel BMR. Prevalence and Burden of Illness of Rome IV Irritable Bowel Syndrome in the United States: Results From a Nationwide Cross-Sectional Study. Gastroenterology. 2023 Dec;165(6):1475-1487. doi: 10.1053/j.gastro.2023.08.010. Epub 2023 Aug 16.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Transcutaneous Auricular Vagus Nerve Stimulation (ta-VNS) in people with Irritable Bowel Syndrome (IBS-C), run by West Virginia University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 11 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 23 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Zain Sobani, MD (304-598-6200, zain.sobani@hsc.wvu.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change From Baseline in IBS Symptom Severity Scale (IBS-SSS) Score at Day 60 (time frame: Baseline to Day 60). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07662083, which also lists 7 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Jun 2026.