{"id":89551,"date":"2026-03-27T12:12:57","date_gmt":"2026-03-27T18:12:57","guid":{"rendered":"https:\/\/www.uchealth.org\/today\/?p=89551"},"modified":"2026-04-06T16:19:52","modified_gmt":"2026-04-06T22:19:52","slug":"does-marijuana-work-as-medicine-clinical-trials-testing-question","status":"publish","type":"post","link":"https:\/\/www.uchealth.org\/today\/does-marijuana-work-as-medicine-clinical-trials-testing-question\/","title":{"rendered":"Does marijuana work as medicine? Clinical trials aim to find answers."},"content":{"rendered":"
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\"Leaders
Leaders in the marijuana industry says cannabis can help with all sorts of health problems. Medical researchers are playing catch-up, and it\u2019s not easy to do gold-standard clinical trials. Photo: Getty Images.<\/figcaption><\/figure>\n

Study after study is having a hard time finding scientific evidence that marijuana is useful as a medical therapy.<\/p>\n

Two recent<\/a> reports<\/a> concluded that marijuana doesn\u2019t help with mental health conditions. A November 2025 study<\/a> in the prestigious Journal of the American Medical Association (JAMA) considered a wider range of maladies and conditions. Its conclusions didn\u2019t mince words.<\/p>\n

\u201cEvidence from randomized clinical trials does not support the use of cannabis or cannabinoids for most conditions for which it is promoted,\u201d the authors wrote. \u201cEvidence is insufficient for the use of cannabis or cannabinoids for most medical indications.\u201d<\/p>\n

Yet\u00a047 states,<\/a>\u00a0including Colorado,\u00a0allow medical marijuana.<\/span><\/p>\n

So, does marijuana work for medical maladies?<\/p>\n

Two University of Colorado Anschutz School of Medicine<\/a> researchers who are currently doing three marijuana studies are trying to help answer that question.<\/p>\n

The challenge is that medical experts in the U.S. have not been allowed to do the most rigorous, \u201cgold-standard\u201d research that would provide answers about marijuana\u2019s effectiveness to help with health challenges.<\/p>\n

\u201cOne of the things we\u2019re trying to address through our research is to do the placebo-controlled, randomized studies that help inform further reviews and analyses of clinical effects,\u201d said Dr. Rachael Rzasa Lynn<\/a>, an associate professor<\/a> of anesthesiology who cares for patients at UCHealth University of Colorado Hospital<\/a>.<\/p>\n

Does marijuana work for chronic pain?<\/strong><\/h2>\n
\"Dr.
Dr. Rachael Rzasa Lynn, an anesthesiologist and pain management expert, says patients tell her cannabis helps manage their pain. She aims to see if those impressions hold in randomized controlled clinical trials, medical science\u2019s gold standard. Photo courtesy of Dr. Rachael Rzasa Lynn.<\/figcaption><\/figure>\n

Rzasa Lynn and Emily Lindley<\/a>, an associate professor of orthopedics with a doctorate in neurobiology, have their doubts about the many health claims that marijuana industry leaders tout. For example, marijuana promoters say their products help with a broad array of health problems, including depression, anxiety, insomnia, inflammation, post-traumatic stress disorder, swelling, migraines, cramping, hypertension, arthritis, muscle spasms, mood swings, asthma, anorexia, premenstrual syndrome, ADHD, bipolar disorder, multiple sclerosis, Parkinson\u2019s disease and more.<\/p>\n

The Colorado experts also do not dismiss concerns about cannabis use disorder<\/a>, which is also known as marijuana addiction.<\/p>\n

But Rzasa Lynn is far from alone among doctors whose patients insist that cannabis helps them. And she and Lindley believe we need many more randomized controlled trials to provide answers about whether marijuana has any medical benefits.<\/p>\n

They\u2019re working to do just that, with a focus on chronic pain.<\/p>\n

It\u2019s not easy. Consider Lindley\u2019s first marijuana study<\/a>, a randomized controlled trial comparing the ability of one-off use of vaporized cannabis versus the opioid oxycodone to diminish chronic neck and back pain.<\/p>\n

Marijuana studies face hurdles<\/strong><\/h2>\n

First, there\u2019s the legal elephant in the room: marijuana remains illegal under federal law. The legal status of marijuana may soon be changing. A December 2025 executive order<\/a> aims to reclassify marijuana from a Schedule I drug to Schedule III under the Controlled Substances Act.<\/p>\n

\"Emily
Emily Lindley has been working on clinical research related to marijuana and chronic pain for more than a decade. Photo: University of Colorado Anschutz.<\/figcaption><\/figure>\n

Along with marijuana, Schedule I drugs include heroin and are classified as highly addictive with no accepted medical uses. The marijuana-rescheduling order cited \u201cscientific support for its use to treat anorexia related to a medical condition, nausea and vomiting, and pain.\u201d A 2015 study in JAMA<\/a> found \u201clow quality\u201d evidence that this claim might be true.<\/p>\n

Schedule III drugs have accepted medical uses and a lower risk of dependence than Schedule I or II drugs. They also present far fewer barriers to researchers.<\/p>\n

But for now, marijuana remains a Schedule I drug. So, in addition to standard institutional review board and other approvals typical in medical research, Lindley had to get U.S. Food and Drug Administration investigational new drug approval for the marijuana itself, grown at a National Institute for Drug Abuse\u2019s facility in Mississippi. Lindley\u2019s team and the Colorado Clinical and Translational Sciences Institute<\/a> on the Anschutz Campus worked with the Drug Enforcement Administration to establish safeguards around the handling and dispensation of the marijuana central to the study.<\/p>\n

The safeguards included a new freezer that is bolted to the ground with both external and internal locks, double-lock steel cabinets for room temperature storage, security cameras inside and outside the storage room, and construction of a ventilation system in the exam room where patients would use the Volcano Vaporizer Lindley procured for the study.<\/p>\n

Recruiting patients also proved challenging, Lindley said.<\/p>\n

\u201cOften, people who were really interested in being in the study were already using cannabis for their chronic pain,\u201d she said.<\/p>\n

Despite these obstacles, Lindley and her team have finished the study and are analyzing the data. She aims to publish results later this year.<\/p>\n

Studying oral cannabis for pain management<\/strong><\/h2>\n

Rzasa Lynn is collaborating with Lindley on the other two studies. One considers whether long-term use of oral cannabis or marijuana edibles<\/a> helps chronic back and neck pain; the other focuses on topical cannabis products.<\/p>\n

The oral cannabis clinical trial<\/a> is now recruiting up to 63 people who will take three different treatments for about six weeks each: two cannabis extracts with varying amounts of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), and a placebo. The team aims to capture the data needed to determine whether daily treatment with oral cannabis reduces spine pain compared to a placebo.<\/p>\n

As in all of their studies, the researchers also are tracking harms or side effects of marijuana use.<\/p>\n

Participation from the marijuana industry will likely be important in sorting out the ultimate utility of cannabis in medical treatment because the FDA requirements for an investigational new drug approval are stringent, Rzasa Lynn says.<\/p>\n

\u201cThe reality is, a lot of companies that sell these products aren\u2019t willing to provide that level of data, that level of manufacturing consistency,\u201d she said. \u201cBut some of them are. And there are a lot of people who want to do this research.\u201d<\/p>\n

An observational topical cannabis pain management study<\/strong><\/h2>\n

The topical cannabis study<\/a> is, as so many marijuana studies have been, observational. The study doesn\u2019t assign drugs; rather, participants use whatever topical cannabis product they choose. The study team follows them over time, documenting patients\u2019 perceptions of whether the product is helping their pain. Lindley and Rzasa Lynn are more than halfway through an enrollment of about 75 people who have decided to begin using cannabis-containing lotions, creams and other products applied to the skin rather than inhaled or ingested.<\/p>\n

\u201cI have patients all the time who tell me that certain products work really well for them, but these things haven\u2019t been studied,\u201d Rzasa Lynn said.<\/p>\n

The aim is to understand if and how well different topicals sold online and in dispensaries, natural foods stores, pharmacies, and elsewhere help manage pain. But also, blood samples will help the research team determine whether and to what extent THC, CBD, and other cannabinoids end up in the bloodstream.<\/p>\n

\u201cThere\u2019s this perception that topical products are a lot safer than inhalation or other routes of administration, and we think that\u2019s probably true, and that the effects are via local tissue interaction and not systemic,\u201d Lindley said. \u201cBut no one has really studied that.\u201d<\/p>\n

One major wrinkle: Because participants cannot bring retail marijuana products onto the University of Colorado Anschutz campus, the team has a mobile pharmacology lab doing house calls to participants\u2019 residences.<\/p>\n

While the blood testing could break new empirical ground, Lindley and Rzasa Lynn are well aware that, as an observational study, it has its limitations. But understanding which cannabis topicals people are using for chronic pain and which may be most effective would open the door to placebo-controlled trials.<\/p>\n

\"The
The mobile pharmacology lab: One of many adaptions required to study potential medical uses for cannabis. Photo courtesy of Emily Lindley\/University of Colorado Anschutz School of Medicine.<\/figcaption><\/figure>\n

As more definitive science emerges, doctors strike a balance<\/strong><\/h2>\n

Anecdotal evidence, observational studies and a few randomized controlled trials led the American College of Physicians to publish guidelines<\/a> for best-practices for marijuana use. The guidelines emphasize discussing potential benefits and harms with patients. These include:<\/p>\n