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CompletedNCT00000251Updated Dec 2, 2015

Effects of Subanesthetic Concentrations of Isoflurane/Nitrous Oxide - 3

A Phase 2 interventional study of 30% N2O and 0.2% isoflurane in Opioid-Related Disorders and Substance-Related Disorders, sponsored by University of Chicago. Completed at 1 site in United States. Open to participants aged 21 Years to 32 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2015-12-02.

Sponsored by University of Chicago · Phase 2, Interventional, and Treatment

Phase
Phase 2
Study type
Interventional
Enrollment
10
Allocation
Randomized
Ages
21 Years to 32 Years
Sex
All
01

Study summary

The purpose of this study is to conduct experiments to examine subjective and reinforcing effects of nitrous oxide. Mood altering and psychomotor effects will be tested on non-drug abusers and preference procedures will be used to assess reinforcing effects. To evaluate the acute and residual effects of subanesthetic concentrations of isoflurane/nitrous oxide combinations in healthy volunteers.

02

Conditions studied

  • Opioid-Related Disorders
  • Substance-Related Disorders

Keywords

  • nitrous oxide
  • isoflurane
  • subjective effects
  • psychomotor
  • healthy volunteer
  • drug interaction
03

In context

Opioid-Related Disorders

1,439 studies on the registry are indexed under Opioid-Related Disorders; 291 are open to participants now.

This study's enrollment of 10 is below the median of 62 across 1,145 interventional studies indexed under Opioid-Related Disorders.

Browse Opioid-Related Disorders studies →

Lead sponsor

University of Chicago is the lead sponsor of 924 studies on the registry; 186 are open to participants now.

Of its 102 completed or terminated interventional studies of FDA-regulated products, 71 (70%) have results posted.

Browse University of Chicago studies →

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
21 Years to 32 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Eligibility criteria

Please contact site for information.

05

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Crossover assignment
Masking
Single (Participant)
Enrollment
10 participants (actual)

Study arms

  • Placebo comparator
    Placebo

    Subjects inhale 100% oxygen

    Other: 100% oxygen

  • Active comparator
    30% N2O

    Subjects inhale 30% N2O

    Drug: 30% N2O

  • Active comparator
    0.2% isoflurane

    Subjects inhale 0.2% isoflurane

    Drug: 0.2% isoflurane

  • Active comparator
    0.4% isoflurane

    Subjects inhale 0.4% isoflurane

    Drug: 0.4% isoflurane

  • Active comparator
    0.2% isoflurane + 30% N2O

    Subjects will inhale a combination of 0.2% isoflurane and 30% N2O

    Drug: 30% N2O · Drug: 0.2% isoflurane

  • Active comparator
    0.4% isoflurane + 30% N2O

    Subjects will inhale a combination of 0.4% isoflurane and 30% N2O

    Drug: 30% N2O · Drug: 0.4% isoflurane

Interventions

06

What researchers measure

Primary outcomes

  1. Logical reasoning test

    Time frame: 15 & 30 min inhalation and 5, 30, & 60 min post inhalation

  2. Free recall memory test

    Time frame: 15 & 30 min inhalation and 5, 30, & 60 min post inhalation

  3. Auditory reaction time

    Time frame: 15 & 30 min inhalation and 5,30 & 60 min post inhalation

  4. Digit symbol substitution test

    Time frame: 2,15 & 30 min inhalation and 5,30 & 60 min post inhalation

07

Study locations

1 site
  • University of Chicago, Anesthesia & Critical Care
    Chicago, Illinois 60637, United States
08

References and documents

Publications

  • Zacny JP, Yajnik S, Lichtor JL, Klafta JM, Young CJ, Thapar P, Rupani G, Coalson DW, Apfelbaum JL. The acute and residual effects of subanesthetic concentrations of isoflurane/nitrous oxide combinations on cognitive and psychomotor performance in healthy volunteers. Anesth Analg. 1996 Jan;82(1):153-7. doi: 10.1097/00000539-199601000-00028. PubMed 8712393 ↗
  • Whelan J, Hackshaw A, McTiernan A, Grimer R, Spooner D, Bate J, Ranft A, Paulussen M, Juergens H, Craft A, Lewis I. Survival is influenced by approaches to local treatment of Ewing sarcoma within an international randomised controlled trial: analysis of EICESS-92. Clin Sarcoma Res. 2018 Mar 30;8:6. doi: 10.1186/s13569-018-0093-y. eCollection 2018. PubMed 29610659 ↗
09

Timeline

Tracking since Sep 25, 2026
Not marked actual or estimatedDates not marked actual or estimated

The record gives a start of Apr 1994, a primary completion of Jan 1996 and a completion of Jan 1996. It does not say whether these dates are actual or estimated.

How these figures are worked out, and which studies are left out of them.

Registered
Sep 20, 1999
First posted
Sep 21, 1999
Start
Apr 1994
Primary completionActual
Jan 1996
CompletionActual
Jan 1996
Last update
Dec 2, 2015
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Dec 2, 2015, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT00000251
Lead sponsor
University of Chicago
Collaborators
National Institute on Drug Abuse (NIDA)
Responsible party
Sponsor
First posted
Sep 21, 1999
Start date
Apr 1994
Primary completion
Jan 1996
Completion
Jan 1996
Last update
Dec 2, 2015

Study contacts

James Zacny, Ph.D.
principal investigator · University of Chicago
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Nov 2015. You cannot join it, but the record below documents what was studied.

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Studies of the drugs tested here: Nitrous Oxide · Isoflurane

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