Due to the nature of their work, many agents require special medications that could only really exist at HQ. Because, really, is ibuprofen going to help with the memories of that Sue you've just slain?
Of course not.
A word of caution, however: Many of the medications from the PPC and related canon protectorates tend to not work in Real Life, or at least not how one would want it to work. In fact, attempts at "real" Bleeprin is probably a very bad idea.