Understanding How Opioids Affect the Experiential and Neural Signatures of Social Experiences

The study is a randomized, placebo-controlled design with the opioid antagonist, oral naltrexone. Following random assignment, participants will take 50mg of naltrexone or placebo once a day for 7 days. On days 1 - 7, participants complete reports of their feelings of social connection and mood in order to assess more naturalistic feelings in response to opportunities for social connection outside of the laboratory setting. Additionally, at the end of each day, they complete a physical symptoms questionnaire. On the 7th day, participants will come to the SDSU MRI scanning facility to complete tasks designed to elicit feelings of social connection in the fMRI scanner. After the scan, feelings in response to the scanner tasks will be collected.

NCT Number	NCT05007561
Lead Sponsor	San Diego State University Collaborators: National Institute on Drug Abuse (NIDA)
Conditions	Naltrexone, Placebo
Enrollment	210 participants
Start Date	2021-11-16
Primary Completion	2027-04 (estimated)
Study Completion	2027-07 (estimated)
Updated on ClinicalTrials.gov	2026-04-13