A brief summary:
Proponents of cannabis use in a medical context have often suggested that it is a superior substitute of opioid for chronic pain management. Cannabis owes its analgesic properties to components called cannabinoids, with the two most prominent being cannabidiol (CBD) and tetrahydrocannabinol (THC). Both compounds have similar potential for treating chronic pain, however, while THC is addictive, CBD is not and therefore is of special clinical interest.
These compounds exert biological effects by binding and activating cannabinoid receptors in our bodies.
Two main subtypes of these receptors are type 1 (CB1), which are primarily located in the brain and type 2 (CB2), which are primarily located in the immune system. Therefore, several studies have suggested that cannabis can reduce both neuropathic pain, which is caused by damage or diseases affecting the somatosensory nervous system, by acting on CB1 and inflammatory pain, which is the hypersensitivity to pain caused by inflammation, by acting on CB2. However, the results of some of these studies lack statistical significance and findings from different studies are sometimes inconsistent. In addition, there also exists significant evidence of adverse side effects associated with cannabinoids treatment. For the above reasons, additional clinical research needs to be conducted before definite conclusions on the pain-relieving properties and medical application of cannabis can be reached.