Chronic pain is a complex, severe and debilitating condition which can lead to a considerable reduction in function and quality of life. Patients may present with different forms of chronic pain resulting from a number of identifiable causes, including pain due to lesion or dysfunction of the nerves, spinal cord or brain (neuropathic pain), or persistent pain caused by other non-malignant conditions, such as low-back pain or pain due to inflammation of various arthritic conditions. The prevalence of chronic non-cancer pain or neuropathic pain among Canadian adults is not well known. However, prevalence estimates using large, population-based questionnaires have shown that 4% to 8% of the general population in the developed world experiences neuropathic pain, suggesting that approximately two million Canadians may be affected by this disabling condition. Chronic pain is of particular concern among Canadians aged 65 years and older; based on cross-sectional data from the 1996/1997 National Population Health Survey and the 2005 Canadian Community Health Survey, chronic pain was estimated to affect 27% and 38% of seniors living in households and health care institutions, respectively.
A number of treatments are available for the management of neuropathic pain or chronic non-cancer pain. These include tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors (duloxetine, venlafaxine), anticonvulsants (pregabalin, gabapentin, carbamazepine, phenytoin), topical lidocaine, and opioid analgesics. However, these medications are associated with limited pain relief and numerous adverse effects. The therapeutic use of several synthetic cannabinoid products for the symptomatic relief of chronic pain has also been studied. In particular, a combination of two products, delta-9-tetrahydrocannabinol and cannabidiol (THC:CBD) marketed under the name Sativex® is available for use as a buccal spray. This cannabis-based agent is approved for use in Canada as an add-on therapy for adult patients experiencing muscle spasticity caused by multiple sclerosis (MS), and it has received a Notice of Compliance with conditions for MS-related central neuropathic pain and the treatment of cancer pain unresponsive to opioids.
The purpose of this review is to examine the available published literature relating to THC:CBD buccal spray for the treatment of chronic non-cancer or neuropathic pain in adults.
Disclaimer: The Rapid Response Service is an information service for those involved in planning and providing health care in Canada. Rapid responses are based on a limited literature search and are not comprehensive, systematic reviews. The intent is to provide a list of sources of the best evidence on the topic that the Canadian Agency for Drugs and Technologies in Health (CADTH) could identify using all reasonable efforts within the time allowed. Rapid responses should be considered along with other types of information and health care considerations. The information included in this response is not intended to replace professional medical advice, nor should it be construed as a recommendation for or against the use of a particular health technology. Readers are also cautioned that a lack of good quality evidence does not necessarily mean a lack of effectiveness particularly in the case of new and emerging health technologies, for which little information can be found, but which may in future prove to be effective. While CADTH has taken care in the preparation of the report to ensure that its contents are accurate, complete and up to date, CADTH does not make any guarantee to that effect. CADTH is not liable for any loss or damages resulting from use of the information in the report.
