Does Taurine Supplementation Improve Vascular Function and Orthostatic Responses in Long COVID?

NCT07312409 | Recruiting

• 1 other identifier: Edgell Long COVID trial
• Study Type: observational
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Millions have developed Long COVID (LC), and recent findings show an association between taurine deficiency (an amino acid) and symptoms in LC. Cost-effective and accessible interventions are needed to improve welfare and reduce healthcare costs. We will investigate the efficacy of 12-weeks of taurine supplementation (self-administered), on vascular function and the cardio/cerebrovascular responses to upright posture. We will measure resting vascular function with an EndoPAT device, resting heart rate variability, and the blood pressure, heart rate, and brain blood flow responses to 5 minutes of head-up tilt before and after weeks of taurine supplementation in LC. We hypothesize that the 12 weeks of supplementation will improve both resting vascular function and the responses to upright tilt. In turn, we hypothesize that symptoms will also improve (as measured by questionnaires).

Conditions

Long COVID Syndrome

Keywords

Taurine; Vascular; Long COVID; Orthostatic; Cerebrovascular; Heart rate variability

Outcome Measures

Primary Outcomes (2)

• Orthostatic responses

  Measure cardiovascular and cerebrovascular responses to upright tilt using beat to beat blood pressure, ECG, and transcranial Doppler.

  Baseline and 12-weeks

• Vascular function

  Flow-mediated dilation and EndoPAT response. These techniques concurrently measure endothelial function using the same protocol.

  Baseline and 12-weeks

Secondary Outcomes (1)

• Heart rate variability

  Over the course of 12 weeks

Study Arms (2)

Taurine supplementation

Long COVID patients will self-administer 12-wks of taurine supplementation

Dietary Supplement: Taurine supplementation

Time control

Long COVID patients who are not taking taurine supplementation

Interventions

Taurine supplementation DIETARY_SUPPLEMENT

Participants will self-administer 12-wks taurine supplementation

Taurine supplementation

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Men and women aged 18-65 will be recruited who have been diagnosed by a medical professional with Long COVID, which is defined as persistent symptoms for \>3 months after a COVID infection. Participants will also need to experience orthostatic intolerance, which is the feeling of dizziness or faintness when standing for a prolonged period. Participants must be able to transport themselves to York University and undergo testing which will take approximately 90 minutes. This includes the ability to undergo a tilt table test for 5 minutes. Therefore, any musculoskeletal problems which prevent upright posture will be excluded. Participants must be able to communicate in English and have the ability to be contacted by email or phone throughout the 12-week period. Current smokers will be excluded. Participants who regularly consume energy drinks that contain taurine (more than once per week) will be excluded.

You may qualify if:

• Participants will have had symptoms of Long COVID post-infection for at least 3 months

You may not qualify if:

• Inability to undergo tilt table testing for 5 minutes
• Inability to transport selves to York University from their homes
• Inability to speak English, or provide a translator
• Blood clotting disorders

Sponsors & Collaborators

• Canadian Institutes of Health Research (CIHR): collaborator
• York University: lead

Study Sites (1)

York University

Toronto, Ontario, M3J1P3, Canada

RECRUITING

Related Publications (11)

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MeSH Terms

Conditions

Post-Acute COVID-19 Syndrome

Condition Hierarchy (Ancestors)

COVID-19; Pneumonia, Viral; Pneumonia; Respiratory Tract Infections; Infections; Virus Diseases; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; RNA Virus Infections; Lung Diseases; Respiratory Tract Diseases; Post-Infectious Disorders; Chronic Disease; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Central Study Contacts

Heather Edgell, PhD

CONTACT

14167362100; edgell@yorku.ca

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Target Duration: 12 Weeks
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: December 17, 2025
• First Posted: December 31, 2025
• Study Start: June 1, 2026
• Primary Completion (Estimated): June 30, 2027
• Study Completion (Estimated): December 31, 2027
• Last Updated: June 5, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)