A comprehensive research review examining 10,000 studies has found conclusive evidence that cannabis and cannabinoids are beneficial for treating symptoms like chronic pain, nausea and vomiting, and spasticity.
Cannabis and its cannabinoids can be an effective medicine for treating an array of symptoms and conditions, according to a new comprehensive report from the nation’s top scientists. The nonprofit National Academies of Sciences, Engineering and Medicine (NASEM) summarized the past 16 years of research on the efficacy of medical marijuana in its report, “The Health Effects of Cannabis and Cannabinoids.”
The rigorous and weighty 395-page report is based on the findings of more than 10,700 studies published in peer-review journals since 1999. The 16-person NASEM committee, chaired by Marie McCormick of Harvard T.H. Chan School of Public Health, arrived at nearly 100 research conclusions on what studies indicate are the benefits and risks associated with marijuana.
The report summarizes its conclusions, categorizing each as either conclusive, substantial, moderate, limited, and no or insufficient evidence.
Here’s an overview of the NASEM committee’s findings on the therapeutic efficacy of cannabis or cannabinoids:
Conclusive or substantial evidence (many supportive findings from good-quality studies with no credible opposing findings) indicate that cannabis or cannabinoids are effective:
- For the treatment for chronic pain (cannabis)
- In the treatment of chemotherapy-induced nausea and vomiting (oral cannabinoids)
- For improving patient-reported multiple sclerosis spasticity symptoms (oral cannabinoids)
Moderate evidence (several findings from good-to fair-quality studies with very few or no credible opposing findings) indicate that cannabis or cannabinoids are effective:
- At improving short-term sleep outcomes in individuals with sleep disturbance associated with obstructive sleep apnea syndrome, fibromyalgia, chronic pain, and multiple sclerosis (cannabinoids)
Limited evidence (supportive findings from fair-quality studies, or mixed findings with most favoring one conclusion) indicate that cannabis or cannabinoids are effective:
- For increasing appetite and decreasing weight loss associated with HIV/AIDS (cannabis and oral cannabinoids)
- At improving clinician-measured multiple sclerosis spasticity symptoms (oral cannabinoids)
- For improving symptoms of Tourette syndrome (THC capsules)
- At improving symptoms of posttraumatic stress disorder
- For producing better outcomes (i.e., mortality, disability) after a traumatic brain injury or intracranial hemorrhage
The report found no or insufficient evidence, however, to support or refute that cannabis or cannabinoids are effective for cancer, cancer-associated anorexia, irritable bowel syndrome symptoms, epilepsy, spasticity from spinal cord injury, amyotrophic lateral sclerosis symptoms, chorea associated with Huntington’s disease, motor system symptoms associated with Parkinson’s disease, dystonia, addictive treatment, and schizophrenia.
Arizona physician Dr. Sue Sisley told SF Gate that she found it “unsurprising” that the NASEM didn’t find any evidence of cannabis being effective for cancer or epilepsy, citing a lack of studies due to obstacles caused by cannabis’ Schedule I classification.
“The federal government has systematically impeded efficacy studies,” Sisley told SF Gate.
Berkeley-based physician and cannabis specialist Dr. Frank Lucido echoed Sisley’s sentiments, claiming the review was clearly limited by federal research barriers.
“For epilepsy, it’s a slam dunk,” Lucido told SF Gate, regarding recommending cannabis. “That definitely helps. I’ve seen over 100 kids with seizure or autism, and a lot of them are doing much better with cannabis than multiple harmful medications in the past. It doesn’t work for everybody, but it’s been miraculous for some kids.”
The NASEM study also found “substantial evidence” of a link between smoking marijuana and chronic bronchitis, an increased risk of motor vehicle crashes, and schizophrenia, as well as a link between maternal smoking with low birth weight. “Moderate evidence” shows an association between marijuana use and suicidal ideation, as well as short-term memory, learning and attention impairments. There is also “limited evidence” of a link between marijuana smoking and a highly curable type of testicular cancer, heart attack, stroke, impaired academic achievement, increased rates of unemployment and low wages, impaired social functioning, and pregnancy complications.
You can access the entire NASEM report, “The Health Effects of Cannabis and Cannabinoids,” here.