Cancer patients who use medical marijuana experience less pain and a better quality of life, Israeli researchers report.
And, their new study found, these patients were able to rely less on opioid painkillers, with minimal side effects.
"I hope people pay attention to the results of this study and use cannabis when appropriate for patients who need it," said Dr. Alex Bekker, professor and chairman of the department of anesthesiology at Rutgers New Jersey Medical School, in Newark.
Many doctors are still reluctant to prescribe marijuana for chronic pain, he said.
"Physicians have a difficult time using cannabis, simply because of historical perspective, and it's still federally not authorized," said Bekker, who reviewed the study findings.
A majority of U.S. states and the District of Columbia have legalized medical marijuana.
But because it is still considered illegal by the federal government, it hasn't been approved by the U.S. Food and Drug Administration, and therefore is not covered by government or private health insurance, Bekker explained.
"Articles like this are important to persuade lawmakers that there's something good for a patient and we're not using it for some strange reason, which is the kind of propaganda that's existed for many years," he said.
Pain, depression, anxiety and insomnia all affect patients undergoing cancer treatment and can lead to a poor prognosis, doctors say.
"Traditionally, cancer-related pain is mainly treated by opioid analgesics, but most oncologists perceive opioid treatment as hazardous, so alternative therapies are required," researcher David Meiri said in a written statement. Meiri is an assistant professor at the Technion Israel Institute of Technology, in Haifa.
For the study, his team followed 324 cancer patients who used medical marijuana over six months. The patients experienced a median 20% reduction in pain symptoms, the researchers found. Median means half had greater pain reduction, half had less.
Study participants also reported other benefits.
Anxiety levels dropped by a median 22% and depression severity by 12%. At the same time, quality of life scores rose by a median 14%. In all, about 60% of participants reported improvement in symptoms tied to medical marijuana, the investigators found.
After six months of using medical marijuana, nearly half stopped all other pain drugs, according to the researchers.
"Medical cannabis has been suggested as a possible remedy for appetite loss; however, most patients in this study still lost weight," Meiri said. "As a substantial portion were diagnosed with progressive cancer, a weight decline is expected with disease progression."
He also noted that sexual function improved for most of the men, but worsened for most women.
Bekker said a majority of studies show that medical marijuana improves patients' quality of life. Because the results of this study occurred over six months, it is difficult to believe that they only represent a "placebo effect," he added.
"From what we know, the majority of studies show improvement in quality of life," Bekker said, noting that marijuana may not actually prevent the pain of chronic disease but it makes living with the pain easier.
"Let's say you have chronic pain and you're watching an interesting movie on TV, for two hours you don't think about it, but when the movie is over you start feeling pain again," he said. "Cannabis is the same effect. Pain may be still there and the reduction in pain is not dramatic, but patients cope better with the pain. Quality of life unquestionably improves with cannabis."
For some patients, however, marijuana may not be the best choice for pain relief, he said. That's especially true for those with a history of psychiatric disorders.
The study was published May 20 in the journal Frontiers in Pain Research.
To learn more about medical marijuana, visit the U.S. National Institute on Drug Abuse.
SOURCES: Alex Bekker, MD, PhD, MS, professor and chair, anesthesiology, Rutgers New Jersey Medical School, Newark; David Meiri, PhD, MSc, assistant professor, Technion -- Israel Institute of Technology, Haifa; Frontiers in Pain Research, May 20, 2022