Comparison of the Analgesic Effects of Dronabinol and Smoked Marijuana in Daily Marijuana Smokers

Study Overview
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Brief Summary
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The following study is designed to determine the analgesic efficacy of smoked marijuana (0, 1.98, and 3.56% THC) and oral THC (0, 10, and 20 mg) in the Cold-Pressor Test (CPT), a laboratory model of pain which has predictive validity for clinical use of analgesics. Oral THC (dronabinol) is known to have a slower onset and longer duration of action compared with smoked marijuana. Therefore, the analgesic effects of oral THC is expected to peak later and last longer than effects produced by smoked marijuana.

Detailed Description
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Laboratory animal studies have demonstrated the analgesic effects of drugs which act on the cannabinoid system, however, these effects have et to be clearly elucidated in humans. To better understand the potential clinical application of cannabinoids for pain management, the following study is designed to determine the analgesic efficacy of smoked marijuana (3.56% THC) and oral THC (20 mg) in the Cold-Pressor Test (CPT), a laboratory model of pain which has predictive validity for clinical use of analgesics. Non-treatment seeking marijuana smokers will be recruited for a five-session study during which the analgesic, subjective, and physiologic effects of cannabinoids will be evaluated. Determining the efficacy of cannabinoids in an experimental model of pain will provide important endpoints (i.e., dose, route of administration, time course) or this effect to further investigate the potential role for clinical use of smoked marijuana and/or oral THC as analgesics.

Official Title
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Comparison of the Analgesic Effects of Dronabinol and Smoked Marijuana in Daily Marijuana Smokers

Conditions
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Pain Threshold, Mood

Intervention / Treatment
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* Drug: Placebo capsules
* Drug: Inactive marijuana (0% THC)
* Drug: Low dose Dronabinol
* Drug: High dose Dronabinol
* Drug: Low THC marijuana
* Drug: High THC marijuana


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults between the ages of 21-45 Current marijuana use Able to perform study procedures Women practicing an effective form of birth control Exclusion Criteria: Female subjects who are currently pregnant or breastfeeding Current,repeated illicit drug use other than marijuana Presence of significant medical illness History of heart disease Request for drug treatment Current parole or probation Recent history of significant violent behavior

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo + inactive marijuana (0% THC)<br>Participants received placebo capsules and smoked inactive marijuana (0% THC) on 1 of 5 outpatient sessions in randomized order. | Drug: Placebo capsules<br>* Placebo capsules<br>Drug: Inactive marijuana (0% THC)<br>* Inactive marijuana cigarettes (0% THC) provided by NIDA<br>|
| Experimental: Dronabinol 10 mg + Marijuana (0% THC)<br>Participants received low dose Dronabinol + inactive marijuana (0% THC) on 1 of 5 outpatient sessions in randomized order. | Drug: Inactive marijuana (0% THC)<br>* Inactive marijuana cigarettes (0% THC) provided by NIDA<br>Drug: Low dose Dronabinol<br>* Dronabinol 10mg<br>|
| Experimental: Dronabinol 20 mg + Marijuana (0% THC)<br>Participants received High dose Dronabinol + inactive marijuana (0% THC) on 1 of 5 outpatient sessions in randomized order. | Drug: Inactive marijuana (0% THC)<br>* Inactive marijuana cigarettes (0% THC) provided by NIDA<br>Drug: High dose Dronabinol<br>* Dronabinol 20mg<br>|
| Experimental: Placebo + Marijuana (1.98% THC)<br>Participants received placebo + low THC marijuana (1.98% THC) on 1 of 5 outpatient sessions in randomized order. | Drug: Placebo capsules<br>* Placebo capsules<br>Drug: Low THC marijuana<br>* marijuana cigarettes (1.98% THC) provided by NIDA<br>|
| Experimental: Placebo + Marijuana (3.56% THC)<br>Participants received placebo + smoked high THC marijuana (3.56 % THC) on 1 of 5 outpatient sessions in randomized order. | Drug: Placebo capsules<br>* Placebo capsules<br>Drug: High THC marijuana<br>* Marijuana cigarettes (3.56% THC) provided by NIDA<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain Tolerance | Change in pain tolerance from baseline (in seconds) as a function of drug condition. The cold pressor test was administered during each session to examine changes in pain threshold (how many seconds it takes for a participant to begin feeling pain after cold water immersion). | Within each session lasting approximately 5 minutes, for a total of five sessions | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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oral thc, cannabis, pain, analgesic effects, dronabinol