Reinforcing Effects of Marijuana and Opioids

Modulation of Drug Intake: Evaluation of Opioid and Cannabinoid Interactions on Drug Self-Administration

Status

Completed

Phases

Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT05485012

Enrollment

Registered

2022-08-02

Start date

2023-08-03

Completion date

2025-03-27

Last updated

2026-04-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Marijuana Use, Opioid Use

Keywords

marijuana, opioid, healthy participants, laboratory study

Brief summary

The primary goals of this study are to examine 1) marijuana modulation of oxycodone self-administration and 2) oxycodone modulation of marijuana self-administration, under controlled conditions and across a range of doses for each drug.

Interventions

DRUGMarijuana

Double-blind administration of marijuana

DRUGOpioid

Double-blind administration of an opioid agonist

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

BASIC_SCIENCE

Masking

QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

18 Years to 50 Years

Healthy volunteers

Yes

Inclusion criteria

* Ages 18-50 * Experience with marijuana and opioids * General good health * Willing to live at the University of Kentucky Hospital (research unit) for approx. 6.5 weeks (meals are provided,

Exclusion criteria

* Significant medical complications/conditions

Design outcomes

Primary

Measure	Time frame	Description
Self-Administration of Drug Units Earned	Through a progressive-ratio self-administration model given once per treatment condition throughout each 6 hour session	The number of units of drug (out of a total of 7) earned in each experimental condition. Participants work for some, none, or all of the available drug dose. For each dose condition, the number of drug units completed for drug was pulled from the raw data and averaged to yield one mean (SEM).

Secondary

Measure	Time frame	Description
Peak End-tidal Carbon Dioxide (EtCO2)	This outcome was recorded prior to and in regular intervals after drug administration for the duration of each session (approximately 6 hours).	End-tidal Carbon Dioxide (EtCO2): For each dose condition, the participants' peak value was pulled from the raw data and averaged to yield one mean (SEM). Higher scores indicate greater impairment.
Trough Respiration Rate	This outcome was recorded prior to and in regular intervals after drug administration for the duration of each session (approximately 6 hours).	Respiration rate (number of breaths per minute): For each dose condition, the participants' trough value was pulled from the raw data and averaged to yield one mean (SEM). Lower scores indicate greater impairment.

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORShanna Babalonis, PhD

University of Kentucky

Baseline characteristics

Characteristic	—
Age, Continuous	39.7 years STANDARD_DEVIATION 8.4
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	6 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants
Race (NIH/OMB) Asian	0 Participants
Race (NIH/OMB) Black or African American	2 Participants
Race (NIH/OMB) More than one race	0 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants
Race (NIH/OMB) White	4 Participants
Region of Enrollment United States	6 participants
Sex: Female, Male Female	1 Participants
Sex: Female, Male Male	5 Participants

Adverse events

Event type	EG000 affected / at risk	EG001 affected / at risk	EG002 affected / at risk	EG003 affected / at risk	EG004 affected / at risk	EG005 affected / at risk	EG006 affected / at risk	EG007 affected / at risk	EG008 affected / at risk	EG009 affected / at risk	EG010 affected / at risk	EG011 affected / at risk	EG012 affected / at risk	EG013 affected / at risk	EG014 affected / at risk	EG015 affected / at risk	EG016 affected / at risk	EG017 affected / at risk	EG018 affected / at risk	EG019 affected / at risk	EG020 affected / at risk
deaths Total, all-cause mortality	0 / 8	0 / 7	0 / 6	0 / 7	0 / 7	0 / 6	0 / 6	0 / 6	0 / 6	0 / 6	0 / 6	0 / 6	0 / 6	0 / 7	0 / 8	0 / 7	0 / 6	0 / 7	0 / 6	0 / 6	0 / 6
other Total, other adverse events	2 / 8	0 / 7	0 / 6	0 / 7	0 / 7	1 / 6	1 / 6	0 / 6	0 / 6	0 / 6	0 / 6	1 / 6	1 / 6	0 / 7	1 / 8	0 / 7	0 / 6	1 / 7	0 / 6	0 / 6	1 / 6
serious Total, serious adverse events	0 / 8	0 / 7	0 / 6	0 / 7	0 / 7	0 / 6	0 / 6	0 / 6	0 / 6	0 / 6	0 / 6	0 / 6	0 / 6	0 / 7	0 / 8	0 / 7	0 / 6	0 / 7	0 / 6	0 / 6	0 / 6

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Apr 16, 2026