34 patients were included in this crossover trial which evaluated the effects of tetrahydrocannabinol (THC), cannabidiol (CBD, a 1:1 mixture of THC and CBD, and placebo sublingual spray in management of patients with chronic pain. Patients were randomized to the order in which they received each treatment for 1 week over a 4-week period, after which a 2nd cycle of 1-week treatments over 4 weeks was administered. The participants were compared on pain severity (VAS), sleep duration and quality, and adverse events. The results demonstrated that THC and THC:CBD relieved pain and improved sleep quality compared to placebo.