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Effects of a Range of Naltrexone Doses in Combination With Smoked Marijuana

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ClinicalTrials.gov Identifier: NCT00403117
Recruitment Status : Completed
First Posted : November 23, 2006
Last Update Posted : October 26, 2016
Information provided by (Responsible Party):

Study Description
Brief Summary:
The purpose of this study is to determine if the subjective effects of marijuana will be decreased by low-doses (< 25 mg) of naltrexone and increased by high-doses (> 50 mg) of naltrexone.

Condition or disease Intervention/treatment Phase
Marijuana Smoking Drug: Naltrexone Drug: Marijuana Phase 2

Detailed Description:
Laboratory animal studies demonstrate that endogenous cannabinoids and opioids are closely inter-related. We have completed a series of studies in marijuana smokers showing that a clinically-utilized dose of naltrexone (50 mg) enhanced the reinforcing and subjective effects of orally-administered tetrahydrocannabinol (THC), while a low naltrexone dose (12 mg) blunted the effects of THC. A better understanding of the effects of a range of naltrexone doses in combination with smoked marijuana has important implications for the following reasons: (1) Alcohol- and opioid-dependent patients receive high doses of naltrexone (50-150 mg), which may increase the abuse liability of marijuana, (2) Low-dose naltrexone blunts THC's intoxicating effects, suggesting potential utility as a treatment medication for marijuana dependence. This study will determine if naltrexone (0, 12, 25, 50, 100 mg) administration 45 min prior to marijuana administration (0, 3.9% THC) alters marijuana's subjective, cognitive or physiological effects. Marijuana smokers will spend approximately 5h/day for a total of 10 days in the outpatient laboratory. Participants will visit the outpatient laboratory 2-3 times per week, with a minimum 48-hr interval between sessions to allow for naltrexone clearance. These data will provide important information regarding the clinical use of naltrexone.

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 49 participants
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Basic Science
Study Start Date : December 2006
Primary Completion Date : May 2008
Study Completion Date : August 2010

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Marijuana
U.S. FDA Resources

Arms and Interventions

Arm Intervention/treatment
Experimental: naltrexone, marijuana
Naltrexone (0, 12, 25, 50, or 100 mg) marijuana (3.27 or 0% THC)
Drug: Naltrexone Drug: Marijuana
Placebo Comparator: placebo, marijuana
marijuana (3.27 or 0% THC)
Drug: Marijuana

Outcome Measures

Primary Outcome Measures :
  1. marijuana's subjective effects [ Time Frame: 8 hours ]

Secondary Outcome Measures :
  1. marijuana's cardiovascular effects [ Time Frame: 8 hours ]

Other Outcome Measures:
  1. marijuana's cognitive effects [ Time Frame: 8 hours ]

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   21 Years to 45 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Current marijuana use
  • Able to perform study procedures
  • 21-45 years of age
  • Women practicing an effective form of birth control

Exclusion Criteria:

  • Current, repeated illicit drug use (other than marijuana)
  • Presence of significant medical illness (e.g., diabetes, cardiovascular disease, hypertension, examination, laboratory hepatitis, clinically significant laboratory abnormalities, tests, 12-lead ECG, Mantoux test LFTs > 3x upper limit of normal)
  • History of heart disease
  • Request for drug treatment
  • Current parole or probation
  • Pregnancy or current lactation
  • Recent history of significant violent behavior
  • Previous adverse reaction to naltrexone
  • Major current Axis I psychopathology Psychiatric interview (e.g., major depressive disorder, bipolar disorder, suicide risk, schizophrenia)
  • Current use of any prescription or over-the-counter medication
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00403117

Sponsors and Collaborators
New York State Psychiatric Institute
Research Foundation for Mental Hygiene, Inc.
National Institute on Drug Abuse (NIDA)
Principal Investigator: Margaret Haney, Ph.D. New York State Psychiatric Institute
More Information

Responsible Party: New York State Psychiatric Institute
ClinicalTrials.gov Identifier: NCT00403117     History of Changes
Other Study ID Numbers: 5360
First Posted: November 23, 2006    Key Record Dates
Last Update Posted: October 26, 2016
Last Verified: October 2016

Keywords provided by New York State Psychiatric Institute:
smoked marijuana
marijuana use

Additional relevant MeSH terms:
Marijuana Abuse
Substance-Related Disorders
Chemically-Induced Disorders
Mental Disorders
Narcotic Antagonists
Physiological Effects of Drugs
Sensory System Agents
Peripheral Nervous System Agents