Effects of Smoked Marijuana on Neuropathic Pain
|ClinicalTrials.gov Identifier: NCT00254761|
Recruitment Status : Completed
First Posted : November 17, 2005
Last Update Posted : February 28, 2008
|Condition or disease||Intervention/treatment||Phase|
|Neuropathic Pain||Drug: Cannabis||Phase 1 Phase 2|
The case for marijuana's medical use for pain is primarily from experimental studies with normal subjects, which have yielded conflicting results. Experimental subjects have been shown to have significant dose-dependant antinociception effect that is not reversed by opioid antagonism. In contrast to this positive antinociceptive effect, other experiments demonstrated hyperalgesic activity and probably enhancement of the perception of pain upon acute exposure in chronic users of marijuana.
In addition to studying spontaneous pain antinociception, it would be useful to evaluate the response to marijuana following evoked pain. Such evoked pain is produced by stimulation of the skin that is normally not noxious.
Because of the potential side effects of marijuana administration, one of the aims of the present study is to analyze inter-individual variability and the occurrence of dose-dependant analgesia of marijuana with an eye on defining tolerable dosing in clinical neuropathic pain syndromes.
Comparisons: Neuropathic and experimentally induced pain scores will be compared after the administration of escalating doses of low, high, and placebo marijuana cigarettes as provided by the National Institutes on Drug Abuse (NIDA).
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||28 participants|
|Intervention Model:||Crossover Assignment|
|Masking:||Triple (Participant, Investigator, Outcomes Assessor)|
|Official Title:||A Double Blind, Active Placebo Controlled Crossover Trial of the Antinociceptive Effect of Smoked Marijuana on Subjects With Neuropathic Pain; Correlation With Changes in Mood, Cognition, and Psychomotor Performance|
|Study Start Date :||November 2003|
|Primary Completion Date :||February 2006|
|Study Completion Date :||February 2006|
High dose cannabis (7.5% THC by weight)
Low dose cannabis (3.5% THC by weight)
Placebo Comparator: 3
- Score on a series of pain scales (heat pain threshold, VAS intensity, VAS unpleasantness, pain relief, neuropathic pain scale).
- Number of subjects who are unable to tolerate the high dose without significant side effects.
- Changes in mood, cognitive impairment, and psychomotor performance (mood - VAS happiness, cognition - Digit Symbol Modalities Test, psychomotor performance - Grooved Pegboard Test).
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00254761
|United States, California|
|UC Davis Medical Center|
|Sacramento, California, United States, 95817|
|Principal Investigator:||Barth L Wilsey, M.D.||University of California, Davis|