It takes over one hour for Marinol to reach full systemic effect,  compared to seconds or minutes for smoked or vaporized cannabis.  Some people accustomed to inhaling just enough cannabis smoke to manage symptoms have complained of too-intense intoxication from Marinol's predetermined dosages. [ citation needed ] Many people using Marinol have said that Marinol produces a more acute psychedelic effect than cannabis, and it has been speculated that this disparity can be explained by the moderating effect of the many non-THC cannabinoids present in cannabis. [ citation needed ] For that reason, alternative THC-containing medications based on botanical extracts of the cannabis plant such as nabiximols are being developed. Mark Kleiman , director of the Drug Policy Analysis Program at UCLA's School of Public Affairs said of Marinol, "It wasn't any fun and made the user feel bad, so it could be approved without any fear that it would penetrate the recreational market, and then used as a club with which to beat back the advocates of whole cannabis as a medicine."  Mr. Kleiman's opinion notwithstanding, clinical trials comparing the use of cannabis extracts with Marinol in the treatment of cancer cachexia have demonstrated equal efficacy and well-being among subjects in the two treatment arms.  United States federal law currently registers dronabinol as a Schedule III controlled substance , but all other cannabinoids remain Schedule I , except synthetics like nabilone .