Effects of a Range of Naltrexone Doses in Combination With Smoked Marijuana
Condition: Marijuana Use
MeSH terms: Marijuana Abuse; Marijuana Use
Intervention: Placebo + Inactive Marijuana (0% THC); Placebo + Active Marijuana (3.27% THC); Naltrexone 12 Mg+ Active Marijuana (3.27% THC); Naltrexone 25 Mg + Active Marijuana (3.27% THC); Naltrexone 50 Mg+ Active Marijuana (3.27% THC); Naltrexone 100 Mg+ Active Marijuana (3.27% THC); Naltrexone 12 Mg + Inactive Marijuana (0% THC); Naltrexone 25 Mg + Inactive Marijuana (0% THC); Naltrexone 50 Mg + Inactive Marijuana (0% THC); Naltrexone 100 Mg + Inactive Marijuana (0% THC)
Intervention description: One capsule containing placebo was administered to the participant in a size 00 opaque capsules with lactose filler 45 minutes before marijuana administration.; One capsule containing placebo was administered to the participant in a size 00 opaque capsules with lactose filler 45 minutes before administration of a marijuana cigarette containing 3.27% THC (ca. 800 mg) provided by the National Institute on Drug Abuse.; One capsule containing 12mg Naltrexone was administered to the participant in a size 00 opaque capsules with lactose filler 45 minutes before active marijuana administration.; One capsule containing 12mg Naltrexone was administered to the participant in a size 00 opaque capsules with lactose filler 45 minutes before active marijuana administration.; One capsule containing 25mg Naltrexone was administered to the participant in a size 00 opaque capsules with lactose filler 45 minutes before marijuana administration.; One capsule containing 50mg Naltrexone was administered to the participant in a size 00 opaque capsules with lactose filler 45 minutes before marijuana administration.; One capsule containing 12mg Naltrexone was administered to the participant in a size 00 opaque capsules with lactose filler 45 minutes before inactive marijuana administration.; One capsule containing 25mg Naltrexone was administered to the participant in a size 00 opaque capsules with lactose filler 45 minutes before inactive marijuana administration.; One capsule containing 50mg Naltrexone was administered to the participant in a size 00 opaque capsules with lactose filler 45 minutes before inactive marijuana administration.; One capsule containing 100mg Naltrexone was administered to the participant in a size 00 opaque capsules with lactose filler 45 minutes before inactive marijuana administration.
Intervention MeSH terms: Naltrexone
Phase: Phase 2
Study type: Interventional
Primary purpose: Basic Science
Allocation: Randomized
Intervention model: Single Group Assignment
Masking: Double (Participant, Investigator)
Masking description: double-blind, placebo-controlled
Enrollment: 49.0
Sex: All
Minimum age: 21 Years
Maximum age: 45 Years
Healthy volunteers: Accepts Healthy Volunteers
Keywords: Naltrexone; Smoked Marijuana

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.
    

Eligibility criteria:

        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