Therapeutic properties of cannabinoid drugs and marijuana in several disorders. A narrative review of the literature

Background. Anti-inflammatory, analgesic, anticonvulsant, and other effects have been attributed to cannabis, and so it has been widely used to treat several diseases. Objective. To assess the use and therapeutic effects of cannabinoid drugs and the cannabis plant in several diseases. Method. We carried out a narrative review of the literature that has reported the use of the cannabis plant (marijuana) and cannabinoid drugs (nabilone, cannabinol and dronabinol, among others). We conducted a search in Medline, Cochrane, SciELO and other web sites. Clinical, controlled, double-blind and randomized studies were included. The route of administration and the cannabinoid drugs used were assessed too. Results. Thirty-four studies were included. Nabilone was the cannabinoid drug more commonly used (12 studies), followed by delta-9-tetrahydrocannabinol (THC) (11 studies). It was also found that the marijuana plant and cannabinoid drugs were used to treat many symptoms or diseases. Two studies were reported for Gilles de la Tourette's syndrome. Discussion and conclusion. Many scientific studies on the marijuana plant and cannabinoid drugs conclude that these are not as effective as conventional medications and thus their benefits should be taken with caution.