Conditions: Marijuana Dependence
Keywords: Baclofen Marijuana Dependence Marijuana Withdrawal
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 13
Healthy volunteers: yes

Brief summary:
The purpose of this study is to determine if baclofen dose-dependently decreases marijuana's direct effects and symptoms of marijuana withdrawal and thus decreases marijuana relapse.

Detailed description:
Only a small percentage of dependent-marijuana smokers who are seeking treatment for their marijuana use are able to achieve sustained abstinence. The objective of this study is to investigate the interaction between marijuana and the potential treatment medication, baclofen, with the direct goal of using this information to improve marijuana treatment outcome. GABAB agonists such as baclofen have been shown to attenuate the self-administration of cocaine, heroin, alcohol and nicotine (see Cousins et al., 2002; Haney et al., 2006). Baclofen also appears to decrease withdrawal symptoms in heroin and alcohol abusers (Akhondzadeh et al., 2000; Addolorato et al., 2000). The purpose of this study is to determine if baclofen dose-dependently decreases marijuana's direct effects and symptoms of marijuana withdrawal and thus decreases marijuana relapse in our laboratory model. For the purposes of this model, relapse is defined as a return to marijuana use after a period of abstinence. The study will utilize an inpatient/outpatient, counter-balanced design, with each participant maintained on each of three medication conditions for 16 days: placebo and baclofen (60, 90 mg/day). Participants will begin taking capsules during the outpatient phase so that the dose can be incremented up to the maintenance dose prior to the first inpatient day. Further, clinical studies have shown that baclofen is most effective at decreasing cocaine's effects when administered for several weeks. During the inpatient study phases, participants will have the opportunity to self-administer placebo or active marijuana 6 times per day. This study will provide important information of the effect of baclofen as a potential treatment medication for marijuana dependence.

Arms:
arm 1: Baclofen (60mg/day or 90 mg/day): Packaged medication in size 00 opaque capsules with riboflavin filler. Study capsules (0, 20, 30mg) were administered 3 times per day (0900, 1530, 2200).

Marijuana: Participants each received a single marijuana cigarette (provided by the National Institute on Drug Abuse) at each smoking occasion. Marijuana cigarettes were stored frozen in an airtight container and humidified at room temperature for 24 h prior to use. arm 2: Baclofen (60mg/day or 90 mg/day): Packaged medication in size 00 opaque capsules with riboflavin filler. Study capsules (0, 20, 30mg) were administered 3 times per day (0900, 1530, 2200).

Marijuana: Participants each received a single marijuana cigarette (provided by the National Institute on Drug Abuse) at each smoking occasion. Marijuana cigarettes were stored frozen in an airtight container and humidified at room temperature for 24 h prior to use. arm 3: Baclofen (60mg/day or 90 mg/day): Packaged medication in size 00 opaque capsules with riboflavin filler. Study capsules (0, 20, 30mg) were administered 3 times per day (0900, 1530, 2200).

Marijuana: Participants each received a single marijuana cigarette (provided by the National Institute on Drug Abuse) at each smoking occasion. Marijuana cigarettes were stored frozen in an airtight container and humidified at room temperature for 24 h prior to use. arm 4: Baclofen (60mg/day or 90 mg/day): Packaged medication in size 00 opaque capsules with riboflavin filler. Study capsules (0, 20, 30mg) were administered 3 times per day (0900, 1530, 2200).

Marijuana: Participants each received a single marijuana cigarette (provided by the National Institute on Drug Abuse) at each smoking occasion. Marijuana cigarettes were stored frozen in an airtight container and humidified at room temperature for 24 h prior to use. arm 5: Baclofen (60mg/day or 90 mg/day): Packaged medication in size 00 opaque capsules with riboflavin filler. Study capsules (0, 20, 30mg) were administered 3 times per day (0900, 1530, 2200).

Marijuana: Participants each received a single marijuana cigarette (provided by the National Institute on Drug Abuse) at each smoking occasion. Marijuana cigarettes were stored frozen in an airtight container and humidified at room temperature for 24 h prior to use. arm 6: Baclofen (60mg/day or 90 mg/day): Packaged medication in size 00 opaque capsules with riboflavin filler. Study capsules (0, 20, 30mg) were administered 3 times per day (0900, 1530, 2200).

Marijuana: Participants each received a single marijuana cigarette (provided by the National Institute on Drug Abuse) at each smoking occasion. Marijuana cigarettes were stored frozen in an airtight container and humidified at room temperature for 24 h prior to use.

Interventions: intervention 1: Baclofen intervention 2: Marijuana intervention 3: Placebo
Intervention descriptions: intervention 1: Baclofen (60mg/day or 90 mg/day): Packaged medication in size 00 opaque capsules with riboflavin filler. Study capsules (0, 20, 30mg) were administered 3 times per day (0900, 1530, 2200). intervention 2: Marijuana: Participants each received a single marijuana cigarette (provided by the National Institute on Drug Abuse) at each smoking occasion. Marijuana cigarettes were stored frozen in an airtight container and humidified at room temperature for 24 h prior to use. intervention 3: None

Protocol document: