Take Part in Research

Why is the study being conducted: Some people with long-COVID experience exercise intolerance, and breathlessness at rest, and during exercise and fatigue. We know that the carotid bodies may play an important role in these symptoms, as we have shown previously that the carotid bodies are overactive in people with long-COVID.

Study aims: The aims of this study are to investigate whether ‘switching off’ the carotid bodies can improve breathing efficiency during exercise, and reduce hyperventilation at rest, in people with long-COVID.

Where: The NIHR Clinical Research Facility, Bristol, England (https://www.bristolcrf.nihr.ac.uk/getting-here/)

What will happen: Participants will attend the Clinical Research Facility for three visits on separate days. Visit 1 is a screening visit and will involve several questionnaires, a blood pressure and ECG check, a blood sample and lung function and diffusion tests. Visits 2 and 3 will be the same, but a different infusion (dopamine or saline) will be used. We will measure your breathing at rest and during an exercise test on an upright cycle ergometer. If participants need a break during the study visits, or would like a quiet place to rest between, or after the procedures, we can facilitate this within the Clinical Research Facility.

Who: People aged between 18-75 years old who have been diagnosed with long-COVID, and healthy control participants.

Funders/Sponsors: The study is sponsored by the University of Bristol and funded by the Medical Research Council, UK Research and Innovation (MRC, UKRI).

Contact details: If you are interested in taking part, please email and you will be sent more information.

More information: For more information about this study, please visit the study website: Long-COVID and the carotid chemoreflex, or see the entry on the NIHR Be Part of Research website:

Please find a link to our paper published in Nature Communications Medicine: https://pmc.ncbi.nlm.nih.gov/articles/PMC10876702/#CR20