THC found more important for therapeutic effects in cannabis than originally thought
Researchers measure product characteristics and associated effects with mobile app
February 26, 2019
Science Daily/University of New Mexico
Researchers recently solved a major gap in scientific literature by using mobile software technology to measure the real-time effects of actual cannabis-based products used by millions of people every day.
Contrary to popular media-reports and scientific dogma, the psychoactive chemical, tetrahydrocannabinol or "THC," showed the strongest correlation with therapeutic relief and far less evidence for the benefits of relying on the more socially acceptable chemical, cannabidiol or "CBD."
In a new study titled, "The Association between Cannabis Product Characteristics and Symptom Relief," published in the journal Scientific Reports, UNM researchers Sarah See Stith, assistant professor in the Department of Economics, and Jacob Miguel Vigil, associate professor in the Department of Psychology, found that THC and CBD contents were the most important factor for optimizing symptom relief for a wide variety of health conditions.
The findings were based on the largest database of real-time measurements of the effects of cannabis in the United States, collected with the ReleafApp, developed by co-authors Franco Brockelman, Keenan Keeling and Branden Hall.
Since its release in 2016, the commercially developed ReleafApp has been the only publicly available, incentive-free app for educating patients on how their type of product (e.g., flower or concentrate), combustion method, cannabis subspecies (indica, sativa, and hybrid), and major cannabinoid contents (THC and CBD) affect their symptom severity levels, essentially providing invaluable user feedback on their health status, medication choices, and the clinical outcomes of those choices as measured by symptom relief and side effects.
The study aimed to address the practical questions of knowing how fundamental characteristics of currently available and frequently used cannabis products, characteristics that often influence consumer choices, affect health symptom intensity levels. The average patient, across the roughly 20,000 measured user sessions and 27 measured symptom categories ranging from depression to seizure activity, showed an immediate symptom improvement of 3.5 points on a 0-10 scale. Dried flower was the most commonly used product and generally associated with greater symptom improvement than other types of products.
Cannabis is rapidly gaining popularity as a mid-level analgesic and promising substitute for prescription opioids and other classes of medications, which often carry undesirable side effects, dangerous drug interactions and risk of death. Presently, federal barriers restrict researchers from conducting cannabis administration studies in the U.S.
"We were able to fill the most significant absence in the previous medical literature, understanding the 'efficacy, dose, routes of administration, or side effects of commonly used and commercially available cannabis products in the United States,'" said Vigil, quoting from the recently released report from the National Academies of Sciences, Engineering, and Medicine, Committee on the Health Effects of Marijuana.
By studying products containing both THC and CBD, the authors were able to analyze the relative importance of these cannabinoids for symptom relief and side effect prevalence, advancing previous research examining either chemical in the absence of the other. One of the most striking patterns in the current results was that THC was generally associated with a more intense user experience, as measured by symptom relief and the prevalence of both positive and negative side effects.
"Despite the conventional wisdom, both in the popular press and much of the scientific community that only CBD has medical benefits while THC merely makes one high, our results suggest that THC may be more important than CBD in generating therapeutic benefits. In our study, CBD appears to have little effect at all, while THC generates measurable improvements in symptom relief. These findings justify the immediate de-scheduling of all types of cannabis, in addition to hemp, so that cannabis with THC can be more widely accessible for pharmaceutical use by the general public," said Vigil.
"More broadly understanding the relationship between product characteristics and patient outcomes is particularly important given the lack of medical guidance received by medical cannabis patients," said Stith. "Most receive only a referral for cannabis treatment from their healthcare provider with all other treatment advice coming from prior recreational experience, the internet, social interactions, and/or often minimally trained personnel working in dispensaries.
"This is very different from how patients receive treatment using conventional pharmaceuticals that come with clear dosing instructions and a standardized, uniform product," she added.
The authors caution that cannabis use does carry the risks of addiction and short-term impairments in cognitive and behavioral functioning, and may not be effective for everyone.
"However, I have seen many people use it as a primary medication for a full spectrum of health conditions as part of their broader desire to gain more control over their healthcare treatment," says Vigil, a perspective that seems to gaining momentum as cannabis appears to be re-emerging as one of the most widely used medications in the U.S.
This investigation was supported in part by public donations to the University of New Mexico Medical Cannabis Research.
https://www.sciencedaily.com/releases/2019/02/190226112353.htm
Cannabinoid drugs make pain feel 'less unpleasant, more tolerable'
September 19, 2018
Science Daily/Syracuse University
Researchers in the College of Arts and Sciences have determined that cannabinoid drugs do not appear to reduce the intensity of experimental pain, but, instead, may make pain feel less unpleasant and more tolerable.
Martin De Vita G'17, a doctoral candidate in the clinical psychology program, is the lead author of a highly anticipated paper on the subject in JAMA Psychiatry (American Medical Association, 2018).
The paper, whose publication coincides with "Pain Awareness Month," represents the first systematic review of experimental research into the effects of cannabis on pain.
"Cannabinoid drugs are widely used as analgesics [painkillers], but experimental pain studies have produced mixed findings," says De Vita, who studies interactions between substance use and co-occurring health conditions. "Pain is a complex phenomenon with multiple dimensions that can be affected separately."
Cannabinoids are chemical compounds that give the Cannabis plant its medical and recreational properties. Marijuana -- a mixture of dried, crumbled parts from the plant -- contains hundreds of these compounds, of which Tetrahydrocannabinol, or THC, is the best known.
"THC is the primary psychoactive compound in marijuana and, along with CBD [also known as cannabidiol, a naturally occurring constituent of cannabis] has been the focus of most medicinal use and research," says Associate Professor Emily Ansell, the study's senior author and director of the University's Research Lab on Personality, Addiction and Trauma (REPEAT).
When ingested, THC binds to receptors in the brain that control pleasure, time perception and pain. This activity boasts the production of dopamine -- what Ansell calls the "feel-good chemical," resulting in euphoria or relaxation.
Although the use of cannabis for medical purposes is legal in more than 30 states, the U.S. Drug Enforcement Administration still considers it a Schedule I drug, with no accepted medical use and a high potential for abuse. This classification, De Vita says, poses a significant challenge to researchers interested in cannabis' therapeutic effects.
Thus, high-quality evidence supporting the effectiveness of cannabis in treating chronic pain has yet to be established.
"Patients reliably endorse the belief that cannabis is helpful in alleviating pain; however, its analgesic properties are poorly understood," says De Vita, also a student therapist in the Syracuse VA Medical Center's PTSD clinic and a graduate researcher in the University's REPEAT Lab and Alcohol Research Lab. "Experimental pain studies of cannabinoid analgesia in healthy adults have produced mixed results."
De Vita and his co-authors in the Department of Psychology -- doctoral candidate Dezarie Moskal, Professor Stephen Maisto and Ansell -- initially identified more than 1,830 experimental studies on cannabis that had been conducted in North America and Europe over a 40-year period. They whittled the group down to 18 studies, and extracted data from more than 440 adult participants.
The team found that cannabinoid drugs were associated with modest increases in experimental pain threshold and tolerance, no reduction in the intensity of ongoing experimental pain, reduced perceived unpleasantness of painful stimuli and no reduction of mechanical hyperalgesia.
"What this means is that cannabinoid analgesia may be driven by an affective, rather than a sensory component. These findings have implications for understanding the analgesic properties of cannabinoids," De Vita says.
Adds Ansell: "The studies predominantly focused on THC varieties, so it is unclear whether or not other cannabinoids may have resulted in different experimental effects on pain."
The first meta-analytic review of its kind, Syracuse's study closely followed published guidelines for conducting and reporting systematic reviews, as well as a pre-registered protocol to enhance transparency. Two independent reviewers also examined the data separately.
"The mean quality and validity score across the studies was high, and analyses did not suggest publication bias," De Vita says.
Whereas the study was limited to experimental (i.e., laboratory induced) pain, the group hopes to expand their line of research into clinical and neuropathic pain.
Clinical pain usually is associated with a progressive, non-malignant disease; neuropathic pain is synonymous with disease or damage to the nervous system, resulting in tissue injury.
The researchers also are interested in studying dynamic pain processes, different types and doses of cannabinoids, and the role of recreational cannabis use.
"The cumulative research synthesized in our review has helped characterize how cannabis and cannabinoids affect different dimensions of pain reactivity," De Vita adds. "It may underlie the widely held belief that cannabis relieves pain. For now, we still have much to learn."
https://www.sciencedaily.com/releases/2018/09/180919111454.htm