One of the most popular recurring topics on the Cornerstone blog is pain management, and for good reason; currently available pain treatment options may go a long way toward reducing pain, but most individuals with chronic pain still report unmet treatment needs. One relevant issue is that multiple sources contribute to pain, and therefore, a single “magic bullet” pain medication does not exist that is capable of treating all sources. As medical science advances, part of researchers’ collective job is elucidating what other pain treatments might be effective and worth adding to the rotation of commonly used painkillers.
As readers know, researchers have identified both THC and CBD as potential pain treatments, with CBD’s anti-inflammatory effects making it an especially good candidate for pain stemming from inflammation (such as in arthritis). Cannabinoids such as CBD represent a great treatment option because abuse potential is relatively non-existent. Opiate-based medicines on the other hand, such as morphine, must be carefully controlled. Doctors are frequently put in the position of evaluating a patient’s pain and choosing whether to prescribe opiates or to withhold that medication to prevent abuse, addiction, and drug trading. That decision can be difficult, and the more non-abusable drugs in a doctor’s arsenal, the more likely pain will be treated effectively.
Lately, as medical research delves deeper into the world of cannabinoids and the body’s own endocannabinoid system, the emerging consensus is that new cannabinoids could be created that are even more effective at reducing pain than cannabis itself. For instance, cannabinoids that lack psychoactive effect while still decreasing pain, or beyond that, enzyme inhibitors that allow the body to keep more of its natural cannabinoids in proper places. Unfortunately, while this represents an eventual goal of cannabinoid science, the latest attempt at testing enzyme inhibitors in France led to disaster. One thing is certain: these treatments are years away and even a successful treatment will have to jump through multiple legal hurdles. In the meantime, the majority of patients hoping to benefit from the pain-reducing effects of cannabinoids have only one legal option: using whole cannabis or some derivative/concentrate of cannabis.
So how effective is whole cannabis? Aside from molecular studies and petri dishes, how effective is vaporizing cannabis in treating pain? Does cannabis actually reduce pain in the way that a normal patient would use it? One study, from the University of California, set out to answer this question directly, by asking patients with treatment-resistant chronic pain to vaporize cannabis. Specifically, researchers selected 42 patients to receive four puffs of vaporized cannabis and an additional 4-8 puffs three hours later. True to medical cannabis culture, researchers selected the popular Storz and Bickel Volcano vaporizer as the test device and established a method to standardize the puff amount. This method required participants to prepare for each puff by holding the mouthpiece close to their mouths, then to inhale for five seconds on cue, then to hold the vapor (without exhale) for an additional ten seconds, and finally to repeat for another puff at 40 seconds on the dot. Readers can confirm that this model is likely similar to their own usage, albeit without the rigorous timing to ensure uniform puffs between participants.
Regardless, one of the difficulties in evaluating pain treatment is steering around the placebo effect, or the tendency for individuals who believe something to be effective to feel that it is effective. To control for this tendency, researchers randomly sorted patients to be given cannabis at THC concentrations of 0, 2.9%, and 6.7% THC respectively. These cannabis samples, vaped in single loads of 0.4 grams cannabis each at 365 Fahrenheit, were acquired from the University of Mississippi, which runs a cannabis supply program administered by the National Institute on Drug Abuse (NIDA). While these samples may not be the high THC samples obtainable from dispensaries, which are sometimes upwards of 20% THC, this method of sourcing cannabis allowed the research team to acquire a known, consistent product. Dosage was randomized and provided by members of the research team not administering the tests to attempt to prevent any bias from occurring. Thus, some participants received no THC at all, which therefore allows the results to be more robust and to remove placebo effect as much as possible.
Before and after administration, patients completed an 11 point pain intensity numerical rating scale (0-11, with a response of “0” representing no pain). By comparing scores before and after, researchers could evaluate the pain reduction observed in comparison to dose of cannabis. In particular, researchers were interested in the number of patients achieving a reduction of pain intensity of 30% or more. This reduction is thought to be practically significant in pain treatment, considering that the actual pain reduction is probably less due to placebo effect.
The results seemed to indicate conclusively that, yes, vaporized whole plant cannabis is indeed effective at significantly reducing pain. While 18 patients reported at least a 30% drop in pain while on placebo, 26 reported that reduction on both lower and higher concentrations of THC in whole plant cannabis. The number of puffs needed to achieve this level was on average between three and four. Additionally, and perhaps most importantly, even when positive psychological effects of cannabis were rated and controlled for, the pain-reducing effect remained statistically significant (or to simplify that: being “high” did not account for the decreased pain reported).
Interesting enough, results did not show much variation between the lower dose and higher dose of THC. This suggests that patients do not necessarily benefit from vaporizing large amounts of cannabis, but rather even a small amount could provide the majority of pain benefit while reducing psychoactive symptoms. One explanation could be that THC is not the primary pain-reducing molecule. As our previous articles have discussed, CBD is likely responsible for pain reduction. Unfortunately, CBD amounts in these cannabis samples was not recorded or provided, making it difficult to establish a correlation or test that hypothesis. However, in the case that CBD concentration was equivalent in both samples, this could easily explain the results observed here.
In any case, in the absence of more advanced cannabinoid-based treatments that may be years away from the treatment market, whole plant cannabis appears to provide pain relief when vaporized the way most cannabis users vaporize. We would encourage individuals with treatment-resistant pain to ask their physician about cannabis, specifically high-CBD varieties.
Barth Wilsey, Thomas Marcotte, Reena Deutsch, et al. An Exploratory Human Laboratory Experiment Evaluating Vaporized Cannabis in the Treatment of Neuropathic Pain from Spinal Cord Injury and Disease. Journal of Pain (2016). DOI: 10.1016/j.jpain.2016.05.010