Brain blood‑flow and oxidative effects of a short high‑oxygen breathing with and without vitamin C

Cerebral Hemodynamic Effects of Oxygen and Antioxidants

Not applicable Interventional Erasme University Hospital · NCT07369232

We will test whether giving vitamin C before a 30‑minute bout of 100% oxygen changes brain blood flow and markers of oxidative stress in healthy adults.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment10 (estimated)
Ages18 Years and up
SexAll
SponsorErasme University Hospital Academic / other
Locations1 site (Anderlecht, Brussels Capital)
Trial IDNCT07369232 on ClinicalTrials.gov

What this trial studies

CHEOXANT is a single‑center, randomized, single‑blind, placebo‑controlled crossover physiological trial at Erasme Hospital in Brussels that will enroll 10–15 healthy adult volunteers. Each participant will attend two sessions one week apart and receive either vitamin C or placebo before breathing 100% oxygen for 30 minutes. Investigators will measure blood markers of oxidative stress and circulating microparticles, and track cerebral blood flow, sublingual microcirculation, and skin perfusion to see how hyperoxia affects microcirculation and whether antioxidant pre-treatment alters those effects. The design uses each person as their own control to improve sensitivity for detecting short‑term physiological changes.

Who should consider this trial

Good fit: Ideal candidates are healthy adults over 18 who are non‑smokers, not pregnant, have BMI ≤25, and have no known cardiovascular, neurological, hematological, renal, or immunological disease and no contraindication to oxygen or vitamin C.

Not a fit: People with active medical conditions, current smokers, pregnant women, or those with BMI >25 or contraindications to oxygen or vitamin C are excluded and would not benefit from participation.

Why it matters

Potential benefit: If successful, the findings could show that vitamin C reduces hyperoxia‑related oxidative stress and helps preserve cerebral microcirculation, informing safer oxygen use.

How similar studies have performed: Small physiological and preclinical studies have suggested vitamin C can reduce markers of oxidative stress during hyperoxia, but clinical results have been mixed and this crossover study is relatively novel for directly measuring cerebral hemodynamics in healthy volunteers.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Adults
* Otherwise healthy, without known pathologies in the cardiovascular, neurological, immunological, renal hematological, or vascular systems.

Exclusion Criteria:

* Smokers
* Pregnant women
* BMI \> 25
* Any reason to avoid vit. C
* Any reason to avoid breathing oxygen at high doses

Where this trial is running

Anderlecht, Brussels Capital

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions OxygenHyperoxemiaAntioxidantCerebral AutoregulationOxidative Stressoxygenantioxidantvitamin c
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.