Cannabis sativa L. is an incredibly complex plant that exerts complex effects on the human body. Although there is increasing evidence suggesting that recreational cannabis use, particularly at earlier ages and in higher amounts, adversely impacts the brain, mounting evidence indicates that cannabis or cannabinoids may actually be effective for the treatment of various conditions. However, in the case of cannabis, policy has outpaced science.

To help bridge this gap between policy and science, I launched the Marijuana Investigations for Neuroscientific Discovery (MIND) Program in 2014. The overall goal of the MIND program is to clarify the impact of cannabinoid-based treatments on physical and mental health and to determine the efficacy of cannabinoids for specific conditions. MIND utilizes a variety of ecologically valid research models (e.g., clinical trials, longitudinal/observational studies, and web-based surveys) to address the impact of cannabis on a number of important variables including cognition, brain function and structure, clinical state, conventional medication use, quality of life, pain, sleep, and other health-related measures. In the MIND program’s longitudinal observational studies, interim analyses have revealed that unlike recreational cannabis consumers who typically exhibit poorer performance on cognitive assessments, medical cannabis patients in the current studies generally demonstrate stable or improved performance on measures of executive function and potential normalization of brain activation during frontal/executive tasks. Overall, medical cannabis patients in these studies also report improvements in mood, anxiety, sleep, pain, and quality of life, underscoring the potential of cannabinoid-based therapies.

However, in order to understand the potential of cannabinoid-based treatments, it is crucial to clearly define two of the key players in the conversation. While over 100 phytocannabinoids have been identified, tetrahydrocannabinol (THC) and cannabidiol (CBD) are the most widely known and generally most abundant cannabinoids found in cannabis plants and products. The primary intoxicating constituent of the plant, THC is typically associated with poorer cognitive performance and neural alterations, particularly when used in higher amounts and at younger ages. Interestingly, acute administration studies have revealed biphasic effects of THC on anxiety; although THC is often anxiogenic at higher doses, it can be anxiolytic at lower doses. CBD, a non-intoxicating constituent with a favorable safety profile, is believed to have a wide range of therapeutic properties, including antiepileptic and anti-inflammatory effects. Importantly, CBD has consistently demonstrated anxiolytic effects in both preclinical and human studies. Despite these compelling discoveries, additional research is clearly needed. 

The growing popularity of medical cannabis coupled with increased rates of anxiety, especially in relation to the COVID-19 pandemic, has reignited a long-standing conversation about the potential effects of cannabis on psychiatric symptoms. While there are numerous pharmacological treatments available for anxiety, limited response rates and frequent presence of residual symptoms underscore the need for alternative treatments. 

MIND is proud to have launched the first clinical trial investigating a whole-plant, full-spectrum CBD product for patients with moderate to severe anxiety, and has recently completed the open-label phase of this study. Throughout the four weeks of treatment, our data demonstrate significantly improved ratings of anxiety along with concomitant improvements in mood, sleep, and quality of life. Mirroring results from our observational studies, patients in the clinical trial also demonstrated stable or improved performance on measures of executive function. No serious adverse events were reported, and no patients reported any feelings of intoxication. Interestingly however, findings from the open-label trial suggest that it is possible for some individuals taking hemp-derived, full-spectrum (high-CBD/low-THC) products to test positive for THC, which could have occupational, legal, or treatment implications.

Although findings from the open label phase of the clinical trial are extremely promising,a definitive assessment of this product’s efficacy will be ascertained through the currently underway placebo-controlled, double-blind phase. In addition, while CBD is generally considered safe, one must recognize that it is not a benign substance; individuals choosing to use CBD containing products must be mindful of potential drug-drug interactions with conventional medications. The hope is that our studies will clarify the potential for cannabinoid-based therapies as a viable treatment for anxiety, as well as other medical and psychiatric conditions, while also providing information for clinicians, patients, and policymakers to make informed decisions that are guided by scientific evidence.