An experimental randomized study on the analgesic effects of pharmaceutical-grade cannabis in chronic pain patients with fibromyalgia

Supplemental Digital Content is Available in the Text. This experimental highly controlled trial in 20 patients with fibromyalgia shows that the cannabinoid THC, but not CBD, is effective in the treatment of fibromyalgia pain.
In this experimental randomized placebo-controlled 4-way crossover trial, we explored the analgesic effects of inhaled pharmaceutical-grade cannabis in 20 chronic pain patients with fibromyalgia. We tested 4 different cannabis varieties with exact knowledge on their ∆9-tetrahydrocannabinol (THC) and cannabidiol (CBD) content: Bedrocan (22.4-mg THC