Damn, the CSA is a long ass document.
So, the attorney general can initiate the process of descheduling a drug.
However:
In order to complete the process, the drug must be determined to fit the criteria accordingly, which means approval from the secretary of the department of health and human services. The act doesn't seem to mention the FDA. As an already scheduled substance, that has already been determined to fit schedule I, this would mean he would need HHS review, right?
Well then, maybe he can order him to unschedule it altogether. There is, in the history of the CSA, one drug that was completely descheduled, but I can't remember what it was (a piperazine I think).
I wonder if there's been West Wing type conversations about this in the Obama White House. Although I doubt the repartee was anywhere near as witty as Sorkin's. His characters intimidate me with their mental agility.