Vireo's Rick Simpson Oil (RSO) is a full-spectrum cannabis extract that contains all the cannabinoids, terpenes, and additional compounds of the whole cannabis plant. This full-spectrum composition allows for the entourage effect, where various compounds in the cannabis work synergistically to enhance their therapeutic potential. -- The primary active ingredients in this medication are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD).