Whether marijuana helps with pain is unclear
Daily users with severe pain report worsening health
April 8, 2020
Science Daily/Ohio State University
Medical marijuana users who say they have high levels of pain are more likely than those with low pain to say they use cannabis three or more times a day, a new study finds.
However, daily marijuana users with severe pain also reported their health had become worse in the past year.
The results don't necessarily mean that marijuana is not effective in treating at least some kinds of pain, according to the researchers. But it suggests more research is needed before marijuana is accepted as an effective treatment for severe pain.
"It's not clear if marijuana is helping or not," said Bridget Freisthler, co-author of the study and professor of social work at The Ohio State University.
"The benefits aren't as clear-cut as some people assume."
The study was published recently in the International Journal of Drug Policy.
One issue is the complex relationship between pain, marijuana use and self-reported health, said Alexis Cooke, lead author of the study and postdoctoral scholar in psychiatry at the University of California, San Francisco.
"Having high chronic pain is related to poorer health, so it may be that people who are using marijuana more often already had worse health to begin with," Cooke said.
"There are still a lot of questions to answer."
The study involved a survey of 295 medical marijuana dispensary patients in Los Angeles. The surveys were conducted in 2013, when California allowed marijuana use only for medical purposes.
All participants were asked how often they used marijuana; rated how their current health compared to one year ago (on a five-point scale from "much better" to "much worse"); and were asked two questions about their pain levels. Based on their answers, the researchers rated participants' pain as low, moderate or high.
Among those surveyed, 31 percent reported high pain, 24 percent moderate pain, and 44 percent were in the low-pain category.
Daily marijuana use was reported by 45 percent of the sample, and 48 percent said they used three or more times per day.
The percentage of participants who used marijuana every day did not differ by pain categories. But about 60 percent of those who reported high pain used the drug three or more times a day, compared to 51 percent of those with moderate pain and 39 percent of those in the low-pain group.
Findings showed no association between daily marijuana use and change in health status among those with low levels of pain. But daily marijuana use was linked to worsening health status among those reporting high levels of pain.
However, strangely, there was no association between how often participants used marijuana per day and changes in health status. There's no easy explanation for this, Freisthler said.
"It shows how little we know about marijuana as medicine, how people are using it, the dosages they are receiving and its long-term effects," she said.
People use marijuana for a variety of different types of pain, including cancer, joint pain, HIV and nerve pain. Researchers don't know if marijuana has different effects on different causes of pain, Cooke said.
"Chronic pain is also associated with depression and anxiety. Marijuana may help with these problems for some people, even if it doesn't help with the pain," she said.
In addition, marijuana use seems to help people who have lost their appetite due to pain or nausea caused by cancer drugs.
"It may not be the pain that patients are trying to address," Cooke said.
The results do suggest we need to know more about the link between marijuana and pain relief, Freisthler said.
"Particularly since the opioid crisis, some people have been touting marijuana as a good substitute for opioids for people in pain," she said.
"But our study suggests we don't know that marijuana is helping to address pain needs."
https://www.sciencedaily.com/releases/2020/04/200408145805.htm
Legal marijuana products too strong for pain relief
March 26, 2020
Science Daily/Wake Forest Baptist Medical Center
More than 90% of the legal marijuana products offered in medical dispensaries are much stronger than what clinical studies have shown that doctors recommend for chronic pain relief, according to a study published in the March 26 online edition of the journal PLOS ONE.
To many that may seem like a good thing, but just the opposite is true.
"We know that high-potency products should not have a place in the medical realm because of the high risk of developing cannabis-use disorders, which are related to exposure to high THC-content products," said the study's lead author, Alfonso Edgar Romero-Sandoval, M.D., Ph.D., associate professor of anesthesiology at Wake Forest School of Medicine, part of Wake Forest Baptist Health.
"Several earlier studies showed that levels of up to 5% tetrahydrocannabinol (THC) -- the main psychoactive compound in marijuana that provides pain relief as well as intoxication -- were sufficient to reduce chronic pain with minimal side effects."
The goal of this study was to evaluate the advertised THC and CBD content of legal cannabis products to determine their suitability for medicinal use, and to compare the potency of the products offered in medical and recreational programs.
The researchers recorded the concentrations of THC and cannabidiol (CBD) -- the non-euphoric compound in marijuana -- in all plant cannabis products provided by legal dispensary websites and compared them between or within the states in the study: California, Colorado, Maine, Massachusetts, New Hampshire, New Mexico, Rhode Island, Vermont and Washington. A total of 8,505 cannabis products across 653 dispensaries were sampled.
Romero-Sandoval's team found that most of the products offered in the medical dispensaries in the study had more than 10% THC and that many had 15% or more, the same as what is available in products at recreational dispensaries.
This is problematic because between 60% and 80% of people who use medical marijuana use it for pain relief, Romero-Sandoval said. The higher the concentration of THC the greater risk, not only for developing dependency, but also for developing tolerance more quickly, which means higher and higher concentrations might be needed to get the same level of pain relief.
"It can become a vicious cycle," Romero-Sandoval said.
"Better regulation of the potency of medical marijuana products is critical. The FDA regulates the level of over-the-counter pain medications such as ibuprofen that have dose-specific side effects, so why don't we have policies and regulations for cannabis, something that is far more dangerous?"
This study provides the scientific evidence to help policy makers correct mistakes and to create a better framework to protect patients, he said.
https://www.sciencedaily.com/releases/2020/03/200326144354.htm
Cannabis pain relief without the 'high'
Mechanism of cannabidiol for safe pain relief without side effects
October 24, 2018
Science Daily/McGill University Health Centre
In the wake of cannabis legalization, a team of scientists at the Research Institute of the McGill University Health Centre (MUHC) and McGill University have delivered encouraging news for chronic pain sufferers by pinpointing the effective dose of marijuana plant extract cannabidiol (CBD) for safe pain relief without the typical "high" or euphoria produced by the THC. The findings of their study have been published in the journal PAIN (The Journal of the International Association for the Study of Pain).
Cannabis indica and sativa are the two main cannabis strains that produce the pharmacological principles known as tetrahydrocannabinol (THC) and cannabidiol (CBD). Dr. Gabriella Gobbi's team demonstrated that CBD does not act on the CB1 cannabinoid receptors like THC but through the mechanism that binds specific receptors involved in anxiety (serotonin 5-HT1A) and pain (vanilloid TRPV1). Researchers were able to extrapolate the exact dosage of CBD displaying analgesic and antianxiety properties without the risk of addiction and euphoria classically produced by the THC.
"We found in animal models of chronic pain that low doses of CBD administered for seven days alleviate both pain and anxiety, two symptoms often associated in neuropathic or chronic pain," says first author of the study Danilo De Gregorio, a post-doctoral fellow at McGill University in Dr. Gobbi's laboratory.
Lead author Dr. Gobbi, a researcher in the Brain Repair and Integrative Neuroscience (BRaIN) Program of the RI-MUHC, sees this as advancement for the evidence-based application of cannabis in medicine with CBD offering a safe alternative to THC and opioids for chronic pain, such as back pain, sciatica, diabetic, cancer and post-trauma pain.
"Our findings elucidate the mechanism of action of CBD and show that it can be used as medicine without the dangerous side effects of the THC," says Dr. Gobbi, who is also Professor of Psychiatry at the Faculty of Medicine at McGill University and staff psychiatrist at the MUHC. "This research is a new advancement for an evidence-based application of cannabis in medicine."
Despite widespread public usage, little clinical studies exist on CBD, which became legal in Canada on October 17, 2018, following the passage of Canada's Cannabis Act.
"There is some data showing that CBD provides pain relief for humans but more robust clinical trials are needed ," says Dr. Gobbi, a recent grant recipient for her study of the pharmalogical effects of CBD.
https://www.sciencedaily.com/releases/2018/10/181024163625.htm