Isoflurane at Subanesthetic Concentrations - 6

This study has been completed.
Information provided by (Responsible Party):
University of Chicago Identifier:
First received: September 20, 1999
Last updated: July 23, 2013
Last verified: July 2013

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 test the hypothesis that isoflurane at subanesthetic concentrations does not reduce cold-water immersion pain in healthy volunteers.

Condition Intervention Phase
Opioid-Related Disorders
Substance-Related Disorders
Drug: 40% Nitrous oxide
Other: Sham comparator
Drug: 0.2% isoflurane
Drug: 0.4% isoflurane
Drug: 0.6% isoflurane
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Single Blind (Subject)
Primary Purpose: Treatment
Official Title: Isoflurane at Subanesthetic Concentrations

Resource links provided by NLM:

Further study details as provided by University of Chicago:

Primary Outcome Measures:
  • Pain response [ Time Frame: Post inhalation ] [ Designated as safety issue: No ]
    Effects of inhaled isoflurane on pain from immersion of subject's arm in ice cold water. Nitrous oxide (40%) was used as a positive control to confirm sensitivity of the pain assay.

Enrollment: 10
Study Start Date: January 1995
Study Completion Date: September 1995
Primary Completion Date: September 1995 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Sham Comparator: 0% isoflurane Drug: 40% Nitrous oxide
Used as pain assay positive control
Other: Sham comparator
0% isoflurane in oxygen
Active Comparator: 0.2% isoflurane Drug: 40% Nitrous oxide
Used as pain assay positive control
Drug: 0.2% isoflurane
Active Comparator: 0.4% isoflurane Drug: 40% Nitrous oxide
Used as pain assay positive control
Drug: 0.4% isoflurane
Active Comparator: 0.6% isoflurane Drug: 40% Nitrous oxide
Used as pain assay positive control
Drug: 0.6% isoflurane


Ages Eligible for Study:   21 Years to 34 Years
Genders Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

Please contact site for information.

  Contacts and Locations
Please refer to this study by its identifier: NCT00000254

United States, Illinois
University of Chicago, Anesthesia & Critical Care
Chicago, Illinois, United States, 60637
Sponsors and Collaborators
University of Chicago
Principal Investigator: James Zacny, Ph.D. University of Chicago
  More Information

No publications provided

Responsible Party: University of Chicago Identifier: NCT00000254     History of Changes
Other Study ID Numbers: NIDA-08391-6, R01DA008391, R01-08391-6
Study First Received: September 20, 1999
Last Updated: July 23, 2013
Health Authority: United States: Federal Government

Additional relevant MeSH terms:
Opioid-Related Disorders
Substance-Related Disorders
Mental Disorders
Nitrous Oxide
Anesthetics, Inhalation
Anesthetics, General
Central Nervous System Depressants
Physiological Effects of Drugs
Pharmacologic Actions
Central Nervous System Agents
Therapeutic Uses
Analgesics, Non-Narcotic
Sensory System Agents
Peripheral Nervous System Agents processed this record on April 22, 2014