I get desensitized pretty frequently, as I am allergic to many meds. Most doctors want the desensitization done in ICU as others have said. I have actually found an allergist who does it for me in his office (located across the street from a hospital should anything go wrong.) It is hard to find a doctor willing to do this however. They start an IV heplock on me, just incase they need it, but the desensitization itself is done orally with a liquid suspension. The process usually takes about 8 hours. They start me out at a minuscule dose of the med and increase every 20 minutes for most of the doses...when the doses get larger toward the end there is sometimes 30 minutes to 1 hour between doses. Before every new dose, they take my vitals and I do a PFT (on a small machine they have in the office). By the end of the desensitization you should have received one full prescribed dose of medication. Once the last dose has been administered I hang around for and hour of 2 to make sure I have no reactions, and then I am good to go. Fortunately, I have never had any problems!
Good Luck!!
Good Luck!!