With hundreds of active constituents — including a wide array of cannabinoids and terpenes — cannabis is one of the most therapeutically versatile plants known to humankind. However, because marijuana has long been (absurdly) classified as a Schedule I drug (substances, like heroin and LSD, the government considers to be the most dangerous, while having “no known medical benefits”), conducting research on its medicinal properties has been challenging.
Despite medical marijuana being legalized to varying degrees in more than half of the states in the U.S., barriers to research persist. The National Academies of Science, Engineering, and Medicine recently published, The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research, in which a diverse committee of scientists and researchers documented the barriers to clinical cannabis research, as well as summarizing the evidence we have to date on the therapeutic properties of cannabis. In compiling the study, the committee reviewed more than 10,000 scientific studies.The committee cited the following barriers to research:
The committee cited the following barriers to research:
- Regulatory: Because cannabis is a Schedule I substance, significant regulatory hurdles impede research.
- Access: Researchers are required to acquire “research-grade” cannabis from a single source – a federally created monopoly. Researchers frequently complain that they find it difficult to access the quantity, quality, and type of cannabis product they need.
- Funding: Historically, most funding for research went to sponsor studies focusing on the potential adverse effects of cannabis — not the medical benefits. The committee reported that a more diverse network of research funding sources is needed
Nonetheless, despite the many research obstacles, the National Academies of Science, Engineering, and Medicine’s clinical cannabis-focused committee dutifully reviewed nearly all the research to date on medical marijuana, detailing how strong of evidence exists for the many conditions people use cannabis to treat.
Here’s what they found:
Conclusive or Substantial Evidence
These are the highest levels of evidence. The committee found a significant number of high-quality research — with little risk of bias — that patients using cannabis to treat the following conditions were highly likely to find significant improvement in their symptoms:
- Chronic Pain: Significant evidence suggests a large proportion of patients using cannabis to treat chronic pain experience a significant reduction in pain symptoms.
- Multiple Sclerosis: Many patients find relief from multiple sclerosis-induced spasticity symptoms
- Cancer Care: Conclusive evidence that certain cannabinoids are effective for palliative cancer care, including the prevention or treatment of chemotherapy-induced nausea and vomiting.
Evidence suggests cannabis or cannabinoids may be effective for treating sleep issues in patients suffering from the following:
However, the committee believes more research is still needed, including more randomized control trials and larger studies.
Limited evidence suggests cannabis or cannabinoids may be effective for numerous other symptoms and conditions. “Limited Evidence” doesn’t mean the evidence is bad; it means there are supportive findings from studies, but there continues to be debate and uncertainty due to risks of bias, limited size studies, or other contributing factors.
Limited evidence finds cannabis and cannabinoids may be effective for the following:
- Restoring Appetite or Weight Loss: Some evidence suggests cannabis may be effective in increasing appetite and decreasing weight loss associated with HIV/AIDS (cannabis and oral cannabinoids).
- Multiple Sclerosis: Improving clinician-measured symptoms associated with multiple sclerosis spasticities.
- Tourette Syndrome: THC capsules have been found to potentially improve symptoms related to Tourette syndrome (THC capsules).
- Anxiety: CBD may improve anxiety symptoms, particularly in individuals with social anxiety disorders.
- PTSD: Cannabis may improve symptoms related to posttraumatic stress disorder (PTSD).
There are clearly many other conditions that have been approved by individual states as qualifying conditions, or that patients report having used cannabis to successfully treat. However, for many of these conditions, there simply aren’t enough high-quality studies to support or refute the potential efficacy of cannabis.
Medical Marijuana may not be a panacea for every condition under the sun, but when compared to many of the most popular prescription drugs, cannabis is an exceptional medicine; it’s safer than many medications, with very low risk of toxicity. Nonetheless, it’s high time the federal government reschedules cannabis so we can conclusively document the full potential — including both benefits and risks — of cannabis.