Home-based Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) for IBS Pain

The goal of this clinical trial is to learn the feasibility and safety of using home-based taVNS in young adults with IBS to manage their IBS-related pain and symptoms. It will also learn about participants' experience in using the home-based taVNS intervention. The main questions it aims to answer are:

* Is it feasible to use a home-based taVNS intervention for pain and symptom management among YAs with IBS?
* Is it safe and reported satisfactory to use a home-based taVNS intervention for pain and symptom management among YAs with IBS? Researchers will compare Active to Sham taVNS (a look-alike intervention that contains minimal stimulation) to see if Active taVNS works on managing IBS-related pain and symptoms.

Participants will:

* Take Active or Sham taVNS intervention for a 6-week treatment (twice daily, 30 minutes per session)
* Visit the research lab at the initial setup and the end of the 6-week treatment for checkups and tests
* Keep a diary of their symptoms and the number of times they use the taVNS.

This pilot randomized controlled study aims to evaluate the feasibility, acceptability, adherence, safety, and potential implementation barriers of home-based taVNS intervention in YAs (18-29 years old) diagnosed with IBS. A two-site, two-arm, parallel, proof-of-concept randomized trial will be conducted to assess the feasibility of using the Active taVNS intervention compared with Sham taVNS in managing IBS-related pain and symptoms. Eighty YAs meeting the Rome IV diagnostic criteria of IBS will be recruited and receive either Active or Sham taVNS for pain and symptom management, along with self-management education and their usual treatment and care. After enrollment and a 2-week baseline run-in period, participants will be randomized to the Active or Sham taVNS with a 6-week treatment (30 minutes per session, twice daily for 6 weeks) and be followed up for another 6 weeks of post-treatment. Investigators will assess feasibility through recruitment rates, adherence, factors influencing adherence, safety, satisfaction, and collection of patient-reported outcomes.

Eligibility Criteria:
Inclusion Criteria:

* 18 - 29 years of age;
* Men and women;
* Diagnosis of IBS from a healthcare provider with current report of pain (volunteers asked to bring provider-verification of IBS diagnosis based on Rome IV criteria to initial study appointment);
* Experiencing moderate pain (≥3 out of 10 on numeric rating scale \[NRS\]) at least 4 days of the week and lasting previous three months;
* Daily access to a computer connected to the internet; and
* Able to read and speak English.

Exclusion Criteria:

* Other chronic pain condition;
* Celiac disease or inflammatory bowel disease;
* Diabetes mellitus;
* severe psychiatric condition requiring inpatient treatment in previous 6 months;
* Pregnancy or lactation;
* Regular use of opioids or other illicit substances;
* use of probiotics or antibiotics within 2 weeks from enrollment; and
* any other conditions/contraindications that prohibit the application of taVNS including but not limited to any current or past history of cardiovascular disorders, recent ear trauma, and metal implants above the level of the neck.