Acetazolamide and plasma volume changes at high altitude
HighCycle Study: Effect of Acetazolamide on Plasma Volume During Acute Exposure to High Altitude in Women and Men
This study will see if acetazolamide helps prevent early plasma volume loss and related altitude symptoms in healthy adults who normally live at low altitude.
Quick facts
| Phase | Phase 4 |
|---|---|
| Study type | Interventional |
| Enrollment | 270 (estimated) |
| Ages | 18 Years to 44 Years |
| Sex | All |
| Sponsor | Centre d'Expertise sur l'Altitude EXALT Academic / other |
| Locations | 1 site (Bishkek) |
| Trial ID | NCT07118462 on ClinicalTrials.gov |
What this trial studies
Healthy, non-smoking men and premenopausal women aged 18–44 who were born, raised, and currently live below 1000 m are enrolled. Participants receive either acetazolamide or a matching placebo and undergo controlled high-altitude exposure with physiological measurements taken during the first 24 hours. Investigators measure plasma volume and hemoglobin concentration to characterize early fluid shifts that occur with hypoxia. Key exclusions include pregnancy or nursing, anemia, recent altitude exposure, and use of most hormonal contraceptives.
Who should consider this trial
Good fit: Ideal candidates are healthy, non-smoking men and premenopausal women aged 18–44 who were born, raised, and currently live below 1000 m and can attend the Bishkek study site.
Not a fit: Those who are pregnant or nursing, anemic, using excluded hormonal contraceptives, recently traveled to high altitude, or already live at high altitude are unlikely to qualify or see direct benefit from this study.
Why it matters
Potential benefit: If successful, this could help maintain plasma volume and reduce early altitude-related symptoms like acute mountain sickness for people traveling to high altitude.
How similar studies have performed: Acetazolamide is already used to prevent acute mountain sickness and prior controlled hypoxia studies have shown early plasma volume shifts, but its specific effect on plasma volume during ascent is still being clarified.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Healthy, non-smoking men and women, age 18-44 years, without any disease and need of regular medication (including oral contraceptives). * BMI \>18 kg/m2 and \<30 kg/m2. * Born, raised and currently living at altitudes \<1000 m. * Written informed consent. * Premenopausal women with an eumenorrheic cycle. Exclusion Criteria: * Other types of contraceptvies (contraceptives (hormonal intrauterine device, vaginal ring, subcutaneous injections or implants, among others). * Pregnancy or nursing * Anaemic (haemoglobin concentration \<10g/dl). * Any altitude trip \<4 weks before the study. * Allergy to acetazolamide and other sulfonamides.
Where this trial is running
Bishkek
- National Center for Cardiology and Internal Medicine — Bishkek, Kyrgyzstan (Recruiting)
Study contacts
- Principal investigator: Paul Robach, PhD — EXALT (Centre d'Expertise sur l'Altitude), Grenoble, France
- Study coordinator: Benoit Champigneulle, MD PhD
- Email: BChampigneulle@chu-grenoble.fr
- Phone: +33476769288
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.