Conclusions and Relevance Cannabinoid drugs may prevent the onset of pain by producing small increases in pain thresholds but may not reduce the intensity of experimental pain already being experienced ; instead , cannabinoids may make experimental pain feel less unpleasant and more tolerable , suggesting an influence on affective processes .
Cannabis-induced improvements in pain-related negative affect may underlie the widely held belief that cannabis relieves pain
Importance Cannabinoid drugs are widely used as analgesics , but experimental pain studies have produced mixed findings .
The analgesic properties of cannabinoids remain unclear .
Objective To conduct a systematic review and meta- analysis of the association between cannabinoid drug administration and experimental pain outcomes in studies of healthy adults .
Cannabinoids in the management of difficult to treat pain
This article review s recent research on cannabinoid analgesia via the endocannabinoid system and non-receptor mechanisms , as well as r and omized clinical trials employing cannabinoids in pain treatment .  Tetrahydrocannabinol ( THC , Marinol ® ) and nabilone ( Cesamet ® ) are currently approved in the United States and other countries , but not for pain indications . Other synthetic cannabinoids , such as ajulemic acid , are in development . Crude herbal cannabis remains illegal in most jurisdictions but is also under investigation . Sativex ® , a cannabis derived oromucosal spray containing equal proportions of THC ( partial CB1 receptor agonist ) and cannabidiol ( CBD , a non-euphoriant , anti-inflammatory analgesic with CB1 receptor antagonist and endocannabinoid modulating effects ) was approved in Canada in 2005 for treatment of central neuropathic pain in multiple sclerosis , and in 2007 for intractable cancer pain . Numerous r and omized clinical trials have demonstrated safety and efficacy for Sativex in central and peripheral neuropathic pain , rheumatoid arthritis and cancer pain . An Investigational New Drug application to conduct advanced clinical trials for cancer pain was approved by the US FDA in January 2006 . Cannabinoid analgesics have generally been well tolerated in clinical trials with acceptable adverse event profiles . Their adjunctive addition to the pharmacological armamentarium for treatment of pain shows great promise
Conclusions and Relevance Cannabinoid drugs may prevent the onset of pain by producing small increases in pain thresholds but may not reduce the intensity of experimental pain already being experienced ; instead , cannabinoids may make experimental pain feel less unpleasant and more tolerable , suggesting an influence on affective processes .
Cannabis-induced improvements in pain-related negative affect may underlie the widely held belief that cannabis relieves pain
Importance Cannabinoid drugs are widely used as analgesics , but experimental pain studies have produced mixed findings .
The analgesic properties of cannabinoids remain unclear .
Objective To conduct a systematic review and meta- analysis of the association between cannabinoid drug administration and experimental pain outcomes in studies of healthy adults .