This meta-analysis assesses the efficacy of cannabinoids according to their indication. Randomized controlled trials included dronabinol (synthetic THC), nabilone (cannabinoid analog of THC), cannabidiol (CBD) and nabiximols (Sativex, 2.7 mg THC and 2.5 mg CBD). A total of 152 studies were analyzed, resulting in 84 comparisons for a total of 12,123 participants. In the results, even though there is a significant effect of cannabinoids on chronic pain, only dronabinol and nabiximol show moderate evidence of efficacy according to the authors. The effect on appetite stimulation could be induced by dronabinol with a moderate level of evidence. Regarding spasticity in multiple sclerosis or paraplegia, only nabiximol has proven its effectiveness. In Parkinson’s disease, CBD appears to have an effect on stiffness and remains the most effective treatment for epilepsy. No cannabinoid would be effective against nausea and vomiting induced by chemotherapy despite the effect highlighted in the past. Nabiximol would be the treatment of choice to alleviate sleep disorders, unlike CBD, but the level of evidence is low. Finally, adverse effects are minimal for all cannabinoids studied.
