Emerging research aims to clarify how marijuana might mitigate pain, post-traumatic stress disorder (PTSD), and anxiety. As of now, medical marijuana is legally sanctioned in 31 states, and nine have approved recreational usage. The Marijuana Policy Project approximates that over 2.8 million individuals in the United States use marijuana medicinally. Recreational usage is even higher, with over 22.2 million consumers, according to a 2015 national survey. Neuroscientist Staci Gruber, an associate professor of psychiatry at Harvard Medical School, asserts, “Marijuana is here to stay.” However, research on its therapeutic properties lags far behind its widespread usage, particularly with regards to mental health. Such discrepancy has driven researchers like Gruber to investigate cannabis despite the hindrances presented by its unclear legal status. In 2017, the National Academies of Sciences, Engineering, and Medicine conducted an exhaustive review on the health effects of cannabis and its 113 chemical constituents or cannabinoids. The review discovered that only three therapeutic uses had significant or conclusive evidence: treating chronic pain, mitigating nausea caused by chemotherapy, and reducing the spasticity related to multiple sclerosis. Behavioral pharmacologist Ziva Cooper, one of the review’s authors, observes that there is little known about the therapeutic effects in the human population. Chronic pain is the primary reason people seek medical marijuana—94 percent of Colorado medical marijuana cardholders claimed they had “severe pain.” However, the review revealed that 27 randomized trials, involving approximately 2,500 participants with chronic pain, demonstrated that cannabis and cannabinoids provided significant pain relief compared to a placebo. Cooper also noted that animal studies have indicated that cannabinoids can reduce the dose of opioids needed for pain relief. Research published in JAMA Internal Medicine showed a decrease in prescription opioid use and rates of opioid-related deaths in states where medical marijuana is legalized. To assess the efficacy of cannabis for pain relief, Cooper and her team conducted a double-blind placebo-controlled study on cannabis use in conjunction with opioids. The study found that the combination of cannabis with a very small opioid dose—one that was non-analgesic by itself—provided substantial pain relief. Her upcoming study aims to discover whether tetrahydrocannabinol, THC, the primary psychoactive component of cannabis, is necessary for pain relief or if cannabidiol (CBD), a non-psychoactive cannabinoid, could achieve the same effect. Marcel Bonn-Miller, an adjunct assistant professor of psychology at the University of Pennsylvania, is researching the effects of THC and CBD on PTSD. Years ago, he noticed a discrepancy between the number of patients reporting marijuana use to alleviate their symptoms and the limited published studies on cannabis and PTSD. Currently, PTSD patients are often treated with behavioral therapies, though these treatments don’t work for everyone. Thus, Bonn-Miller is heading two of the largest and longest studies ever done on cannabinoids and PTSD. Mallory Loflin, a research scientist with the Center of Excellence for Stress and Mental Health at the VA San Diego Healthcare System, is launching a study to test the efficiency of CBD in conjunction with prolonged exposure therapy for PTSD patients. Staci Gruber, director of the Cognitive and Clinical Neuroimaging Core at McLean Hospital’s Brain Imaging Center, leads the Marijuana Investigations for Neuroscientific Discovery (MIND) project. MIND investigates the effects of cannabis and cannabinoids on cognitive performance, medication use, sleep, quality of life, and mental health. The studies have revealed improved cognitive performance, reduced clinical symptoms and anxiety-related symptoms, and decreased use of conventional medications in patients using cannabis for medical purposes. Gruber acknowledges the challenges of studying medical marijuana but remains hopeful. “We are in desperate need of empirically sound data.” she says.

Bonn-Miller is at the forefront of two of the most comprehensive studies on cannabinoids and Post-Traumatic Stress Disorder (PTSD). The first is a double-blind controlled trial comparing varying cannabinoids, involving 76 veterans with PTSD. Participants are assigned to one of four groups, receiving either high THC cannabis, high CBD cannabis, a balanced strain or a placebo. The cannabis utilized for the study is cultivated at the University of Mississippi, the sole federally approved source for research labs. Notably, the potency and diversity of cannabis typically consumed often surpasses that grown at the university. In his second initiative, Bonn-Miller aims to compensate for this disparity. Half of the 150 participants in this observational study will use cannabis sourced from Denver dispensaries, while the other half abstain. The team will assess the types of cannabis used and monitor participants’ PTSD symptoms quarterly for a year. Simultaneously, Mallory Loflin, a research scientist at the Center of Excellence for Stress and Mental Health at the VA San Diego Healthcare System, is conducting a double-blind placebo-controlled study to evaluate the effectiveness of CBD in conjunction with prolonged exposure therapy for PTSD. This method is considered a leading PTSD treatment, but it doesn’t always alleviate symptoms and can be emotionally taxing for some patients. Loflin will investigate the potential of CBD to enhance efficacy and tolerance of this therapy. Involving 136 veterans with PTSD, this study is groundbreaking not only for its focus but also its funding source: the Department of Veterans Affairs, marking their first investment in cannabinoid research. Also making strides in the field is Gruber, leading a privately funded project, Marijuana Investigations for Neuroscientific Discovery (MIND). Established in 2014, MIND aims to examine the impacts of cannabis and cannabinoids on various aspects of patients’ health and cognition. As the director of the Cognitive and Clinical Neuroimaging Core at McLean Hospital’s Brain Imaging Center, Gruber has been studying recreational marijuana users for over two decades. However, the MIND program devotes its resources to medical marijuana users—a markedly different demographic. Studies conducted by MIND on patients utilizing cannabis for therapeutic purposes have reported improved cognitive performance and diminished clinical and anxiety symptoms. They also noted a reduction in the use of conventional medications including opioids, benzodiazepines, mood stabilizers, and antidepressants. Encouraged by these findings, Gruber initiated a double-blind clinical trial on patients with anxiety using a high-CBD, whole-plant tincture. Despite some studies suggesting a negative correlation between smoked marijuana and social anxiety, no double-blind placebo-controlled trial has been conducted on CBD and anxiety. Gruber aims for this trial to illuminate crucial data on CBD. While studying medical marijuana still presents formidable obstacles, Gruber remains hopeful. “Navigating this landscape is challenging,” she admits, “but the potential of cannabis and cannabinoid-based therapies for numerous indications, symptoms, and conditions is immense. We urgently need robust empirical data.””

Marcel Bonn-Miller is an adjunct assistant professor of psychology at the University of Pennsylvania Perelman School of Medicine. He is also the research director for the Lambert Center for Study of Medicinal Cannabis and Hemp at Thomas Jefferson University ¹. His research focuses on the interrelations between cannabis use and PTSD, with the aim of informing intervention and prevention strategies ²³⁴.

According to a study published in the Journal of Affective Disorders, cannabis may reduce the severity of PTSD symptoms such as intrusions, flashbacks, irritability, and anxiety ³. The study found that cannabis could help enhance the extinction rate for challenging memories and reduce overall anxiety responses ⁵. Cannabidiol (CBD), one of the active compounds from the cannabis plant, may help reduce and manage symptoms of PTSD in both topical and edible forms ⁴⁶. However, the symptom reductions are not permanent ³.

It’s important to note that the FDA has not approved nonprescription CBD products, and some products may be inaccurately labeled ⁴. THC can increase feelings of anxiety or paranoia in users, so many believe it’s not a safe or effective treatment for PTSD ⁶. It’s advisable to consult a medical professional before using cannabis or CBD products for PTSD treatment.

Learn more:

1. aspenideas.org2. maps.org3. sciencedaily.com4. medicalnewstoday.com5. forbes.com6. marijuanadoctors.com7. herb.co8. leafwell.com