 - The therapeutic modalities of cannabis have received more research attention recently with the discovery of its ability to stimulate appetite and to provide pain and nausea relief in patients with AIDS, cancer, and multiple sclerosis, among other diseases. SativexRegistered Trademark, an experimental drug derived from the marijuana plant, contains tetrahydrocannabinol THC and cannabidiol CBD, both of which affect brain activity. SativexRegistered Trademark is being tested to determine how and to what extent it affects brain activity. 