Medical marijuana for anxiety: Effectiveness, expectations and entourage effects

This research investigates medical marijuana (MM) product utilization patterns and patient preferences when MM is used for the treatment of anxiety in Pennsylvania. Recognizing that anxiety is a qualifying condition for MM in the state, the study enrolled 116 referred subjects into a 12-month observational longitudinal study to characterize the products patients purchase and use over time. The investigation focused on key product constituents—Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), and the terpene limonene—and captured routes of administration across five time points: baseline, 3 months, 6 months, 9 months and 12 months. Product-level data were obtained from the state seed-to-sale MM tracking system, allowing the study to analyze real-world purchases rather than relying solely on patient recall. At baseline, products purchased by participants averaged 27.00% THC, 3.28% CBD, and 0.73% limonene.

By 12 months, the composition of products used by participants shifted: average THC increased to 33.13% (a statistically significant increase, p ≤ 0.05), CBD decreased to 1.64% (a statistically significant decrease, p ≤ 0.05), and limonene rose slightly to 0.88% without a significant change. These shifts indicate a trend among study participants toward higher-THC and lower-CBD products over the year of observation. Routes of administration were similarly tracked and showed evolving preferences. At baseline, purchases were distributed across product types as follows: concentrates 4.83%, flower 18.40%, infused products (such as capsules, tinctures, troches) 22.17%, topical 9.80%, vape 34.54%, and other products 10.26%. At 12 months, utilization patterns shifted to 8.20% concentrates, 23.21% flower, 20.07% infused products, 6.63% topical, 38.05% vape, and 3.84% other products.

The most notable pattern is an increased preference for vape products by 12 months, alongside increases in flower and concentrates and decreases in infused and topical product purchases. Conclusions drawn by the research team highlight an observable increase in THC concentration in the MM products utilized by patients over the study period, contrasted with declines in CBD and minimal change in limonene. Patient preference trends suggest a higher favorability for vape products as a route of administration compared to other MM forms. The investigators note that this preference may be attributable to perceived ease of use and the potential for more immediate relief of anxiety symptoms with vaping. The study provides longitudinal, purchase-based evidence about how patients using medical marijuana for anxiety adjust product selection over time, both in chemical composition and in delivery method, offering insights relevant to clinicians, policymakers, and researchers monitoring real-world MM utilization for anxiety treatment.