Marijuana Dependence
Conditions
Keywords
marijuana, substance abuse, drug abuse, marijuana dependence, drug addiction
Brief summary
The purpose of this study is to examine the impact of a medication called oxytocin on marijuana use and therapy response in people who frequently use marijuana.
Detailed description
Oxytocin has been shown to promote trust, social bonding, and calmness; however, its potential additive effects with a therapy intervention have not been explored in marijuana-dependent individuals. In the proposed study, the impact of intranasal oxytocin on therapy effectiveness and marijuana use outcomes following a brief therapy intervention will be investigated. It is hypothesized that oxytocin administration (vs. placebo) will improve treatment satisfaction and decrease marijuana use.
Interventions
DRUGOxytocin
Subjects will be administered 40 IUs of oxytocin nasal spray or matching placebo prior to two individual sessions of MET.
DRUGSaline
Subjects will be administered 40 IUs of oxytocin nasal spray or matching placebo prior to two individual sessions of MET.
Sponsors
Medical University of South Carolina
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
1. Subjects must be able to provide informed consent and function at an intellectual level sufficient to allow accurate completion of all assessment instruments. 2. Subjects must meet DSM-IV criteria for current marijuana dependence (within the past three months). While individuals may also meet criteria for abuse of other substances, they must identify marijuana as their primary substance of abuse and must not meet criteria for dependence on any other substance (except nicotine) within the last 60 days. 3. Subjects must consent to remain abstinent from alcohol for 24 hours and other drugs of abuse (except nicotine and marijuana) for three days immediately prior to study procedures. Subjects must abstain from marijuana for 24 hours prior to testing. By restricting marijuana use as proposed, subjects should not be under the acute effects of marijuana. 4. Subjects must consent to random assignment.
Exclusion criteria
1. Women who are pregnant, nursing or of childbearing potential and not practicing an effective means of birth control. 2. Subjects with evidence of or a history of significant hematological, endocrine, cardiovascular, pulmonary, renal, gastrointestinal, or neurological disease including diabetes, as these conditions may affect physiological/subjective responses. 3. Subjects with a history of or current psychotic disorder or bipolar affective disorder as these may interfere with subjective measurements. 4. Subjects who pose a current suicidal or homicidal risk. 5. Subjects taking any psychotropic medications, including SRI's or other antidepressants, opiates or opiate antagonists because these may affect test response. Individuals who take stimulants for treatment of ADHD will be allowed to participate. 6. Subjects with any acute illness or fever. Individuals who otherwise meet study criteria will be rescheduled for evaluation for participation. 7. Subjects who are unwilling or unable to maintain abstinence from alcohol and marijuana for 24 hours and other drugs of abuse (except nicotine) for three days prior to study procedures. 8. Subjects meeting DSM-IV criteria for substance dependence (other than nicotine or marijuana) within the past 60 days. 9. Subjects who, in the investigator's opinion, would be unable to comply with study procedures or assessments.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Therapy Session Satisfaction (as Measured by Subjective Report) | Within 5 minutes of completing a 45-60 minute Motivational Enhancement Therapy (MET) session at last session visit | After MET sessions, subjects completed the Session Rating Scale (SRS, Miller et al). This visual analog scale is comprised of 4 items for which participants rate their therapy experience in terms of relationship, goals and topics, approach/method, and overall, with minimum score 0 representing most dissatisfied and maximum score 10 representing most satisfied. Outcome measure reported below represents SRS score at last MET session. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Marijuana Use (as Measured by Subjective Report of Number of Daily Smoking Sessions ) | Self-report of average daily smoking sessions at MET Session 1 and last MET session 3 | Subjects' marijuana use was measured via self-report of number of smoking sessions per day (Time Line Followback). The average number of daily sessions were calculated per group, with data presented below representing the change in amount of daily smoking sessions per group from first MET session to last MET session. |
Countries
United States
Participant flow
Recruitment details
Participants recruited between July 2014 and May 2015 primarily through media and internet advertisements.
Participants by arm
| Arm | Count |
|---|---|
| Oxytocin intranasal administration
Oxytocin: Subjects will be administered 40 IUs of oxytocin nasal spray or matching placebo prior to two individual sessions of MET. | 8 |
| Saline intranasal administration
Saline: Subjects will be administered 40 IUs of oxytocin nasal spray or matching placebo prior to two individual sessions of MET. | 8 |
| Total | 16 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Lost to Follow-up | 2 | 1 |
Baseline characteristics
| Characteristic | Oxytocin | Saline | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 8 Participants | 8 Participants | 16 Participants |
| Gender Female | 3 Participants | 3 Participants | 6 Participants |
| Gender Male | 5 Participants | 5 Participants | 10 Participants |
| Region of Enrollment United States | 8 participants | 8 participants | 16 participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 1 / 8 | 2 / 8 |
| serious Total, serious adverse events | 0 / 8 | 0 / 8 |
Outcome results
Primary
Therapy Session Satisfaction (as Measured by Subjective Report)
After MET sessions, subjects completed the Session Rating Scale (SRS, Miller et al). This visual analog scale is comprised of 4 items for which participants rate their therapy experience in terms of relationship, goals and topics, approach/method, and overall, with minimum score 0 representing most dissatisfied and maximum score 10 representing most satisfied. Outcome measure reported below represents SRS score at last MET session.
Time frame: Within 5 minutes of completing a 45-60 minute Motivational Enhancement Therapy (MET) session at last session visit
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Oxytocin | Therapy Session Satisfaction (as Measured by Subjective Report) | 9.8 units on a scale | Standard Error 0.4 |
| Saline | Therapy Session Satisfaction (as Measured by Subjective Report) | 9.7 units on a scale | Standard Error 0.3 |
Secondary
Marijuana Use (as Measured by Subjective Report of Number of Daily Smoking Sessions )
Subjects' marijuana use was measured via self-report of number of smoking sessions per day (Time Line Followback). The average number of daily sessions were calculated per group, with data presented below representing the change in amount of daily smoking sessions per group from first MET session to last MET session.
Time frame: Self-report of average daily smoking sessions at MET Session 1 and last MET session 3
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Oxytocin | Marijuana Use (as Measured by Subjective Report of Number of Daily Smoking Sessions ) | -1.39 daily smoking sessions | Standard Error 0.42 |
| Saline | Marijuana Use (as Measured by Subjective Report of Number of Daily Smoking Sessions ) | -0.22 daily smoking sessions | Standard Error 0.44 |