Medical researchers at the University of Colorado Anschutz School of Medicine are conducting clinical trials to determine whether marijuana is effective as a medical therapy, according to a March 27 announcement. While leaders in the marijuana industry claim cannabis can help with various health problems, scientific evidence supporting these claims remains limited.
Recent studies, including one published in November 2025 in the Journal of the American Medical Association (JAMA), found that “evidence from randomized clinical trials does not support the use of cannabis or cannabinoids for most conditions for which it is promoted.” The authors also wrote, “Evidence is insufficient for the use of cannabis or cannabinoids for most medical indications.” Despite this, 47 states—including Colorado—allow medical marijuana.
Dr. Rachael Rzasa Lynn, an associate professor of anesthesiology at UCHealth University of Colorado Hospital, said her research aims to provide answers through placebo-controlled, randomized studies. “One of the things we’re trying to address through our research is to do the placebo-controlled, randomized studies that help inform further reviews and analyses of clinical effects,” she said. Alongside Emily Lindley, an associate professor of orthopedics with a doctorate in neurobiology, they are focusing on whether marijuana helps manage chronic pain.
The researchers face several challenges due to federal restrictions on marijuana. Although there may be changes soon following a December 2025 executive order aiming to reclassify marijuana from Schedule I to Schedule III under the Controlled Substances Act—which would ease some barriers—marijuana currently remains illegal federally. This has required additional approvals and security measures for their studies.
Lindley recently completed a study comparing vaporized cannabis and oxycodone for chronic neck and back pain and plans to publish results later this year. Other ongoing projects include examining oral cannabis products and topical applications such as lotions or creams used by patients managing chronic pain.
Rzasa Lynn said many companies selling these products are not willing or able to provide data required by regulators but noted there are those interested in supporting rigorous research: “The reality is, a lot of companies that sell these products aren’t willing to provide that level of data… But some of them are. And there are a lot of people who want to do this research.”
As more definitive science emerges from these efforts, guidelines from organizations like the American College of Physicians may evolve regarding best practices around discussing potential benefits and harms with patients.
