Recruiting
Phase 1
Phase 2

Oxygen & Acetazolamide

Sponsor:

VA Office of Research and Development

Code:

NCT05589753

Conditions

Sleep Apnea

Opioid Use

Sleep Disordered Breathing

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

Interventions

Hyperoxia

Acetazolamide

Study Details

Brief summary:

There is an increased risk for sleep disordered breathing (SDB), sleep-related hypoventilation and irregular breathing in individuals on chronic prescription opioid medications. Almost 30% of a veteran sleep clinic population had opioid-associated central sleep apnea (CSA). The proposal aims to identity whether oxygen and acetazolamide can be effective in reducing unstable breathing and eliminating sleep apnea in chronic opioid use via different mechanisms. We will study additional clinical parameters like quality of life, sleep and pain in patients with and without opioid use. This proposal will enhance the investigators' understanding of the pathways that contribute to the development of sleep apnea with opioid use. The investigators expect that the results obtained from this study will positively impact the health of Veterans by identifying new treatment modalities for sleep apnea.

Conditions

Sleep Apnea

Opioid Use

Sleep Disordered Breathing

Study ID

NCT05589753

Start date

May 2, 2019

Status verified date

Jun, 2026

Completion date

Mar 31, 2027

Anticipated

Primary completion date

Dec 31, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

Inclusion Criteria:

  • Veterans, age 18-89 years
  • Veterans with prescription opioids

Exclusion Criteria:

  • Patients with BMI>40kg/m2 will be excluded to avoid the effects of morbid obesity on pulmonary mechanics and ventilatory control
  • Patients with history of unresolved/untreated cardiac disease, including recent myocardial infarction, recent bypass surgery, untreated atrial and ventricular tachy-bradycardias
  • Congestive heart failure with Cheyne-Stokes respiration (CSR)
  • Current unstable angina
  • Recent stroke
  • Untreated schizophrenia
  • Untreated hypothyroidism
  • Unresolved seizure disorder
  • Severe respiratory, neurological, liver and renal diseases
  • Unstable psychiatric disorders/untreated PTSD
  • Traumatic brain injury
  • Pregnant women
  • Significant sleep disorder such as narcolepsy, parasomnias disorder
  • Failure to give informed consent
  • Patients on tramadol and suboxone/buprenorphine

Study Design

Enrollment

150 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Other

Interventions and Outcome Measures

Arms

experimental: Hyperoxia

Determine the effect of sustained hyperoxia overnight vs room air overnight on ventilatory control during sleep, including the apneic threshold, carbon-dioxide reserve and chemosensitivity measured via pressure support ventilation (PSV) during non-rapid eye movement sleep (NREM) sleep.

experimental: Acetazolamide (ACZ)

Determine the effect of acetazolamide on cerebrovascular responsiveness to CO2 during wake and sleep. Participants will receive oral ACZ therapy for 6 days, While on the medication following studies will be performed - experimental night study, experimental day study, polysomnography night study (PSG).

Interventions

Hyperoxia

The ventilatory effects of brief hyperoxia will be assessed by analyzing control breaths on room air immediately preceding the hyperoxic exposure, and comparing with the primary end-point, nadir minute ventilation breath, immediately following the brief hyperoxic exposure.

Acetazolamide

Participants with sleep apnea will ingest capsules containing either placebo or acetazolamide 500 mg twice a day for 6 days. On the final 4 consecutive nights while still on ACZ, the investigators will perform i) physiology tests and ii) in-lab follow-up PSG.

Primary outcome measure

  • Apneic threshold - a measure of breathing instability [ Time Frame: 2 days to 30 days ]
  • Cerebrovascular responsiveness to carbon-dioxide [ Time Frame: 7 days ]
  • Ventilatory responsiveness [ Time Frame: 2 days to 30 days ]
  • Carbon-dioxide reserve [ Time Frame: 2 days to 30 days ]

Central Contacts and Locations

Central contacts

Ruchi Rastogi, MS

(313) 576-4464ruchi.rastogi@va.gov

Locations

John D. Dingell VA Medical Center, Detroit, MI

Recruiting

Detroit, Michigan, United States, 48201-1916

Contacts

Ruchi Rastogi, MS

(313) 576-4464ruchi.rastogi@va.gov

Principal Investigator:

Susmita Chowdhuri, MD MS

More Information

Sponsor

VA Office of Research and Development

Last update posted

Jul 1, 2026

Last verified

Jun, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by VA Office of Research and Development on 2026-07-01.