NCT00142727

Opioid Agonist and Antagonist Effects on Opioid Dependence

The Variability of Agonist and Antagonist Effects as a Function of Level of Physical Dependence

• Status: Terminated
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 16 (estimated)
• Sponsor: National Institute on Drug Abuse (NIDA) · NIH
• Sex: All
• Age: 18 Years – 55 Years
• Healthy volunteers: Not accepted

Summary

The purpose of this study is to examine the acute agonist and antagonist effects of a full opioid agonist medication, an opioid antagonist medication, and a partial opioid agonist medication in individuals who have different levels of physical opioid dependence.

Detailed description

The pharmacological effects of opioids in opioid dependent individuals can vary as a function of the characteristics of the opioid being studied (e.g., whether it is an agonist, partial agonist, or antagonist; the dose administered; and the route of administration). Another important set of factors influencing the effects produced by opioids is the characteristics of the organism to which the opioid is being administered. One such characteristic is the level of physical dependence in individuals. Participants in this study will be maintained on different dose levels of an opioid agonist (methadone). The participant will be challenged with a prototypic opioid agonist, antagonist, and a mixed agonist-antagonist with partial agonist features in order to determine the effects that each has on the human body.

Conditions

• Opioid-Related Disorders

Interventions

Type	Name	Description
DRUG	Methadone
DRUG	Full opioid agonist
DRUG	Partial opioid agonist
DRUG	Opioid antagonist

Timeline

• Start date: 2004-01-01
• Completion: 2006-02-01
• First posted: 2005-09-02
• Last updated: 2017-01-12

Locations

1 site across 1 country: United States