Chaos, I think you are right that in-hospital IV's are charged by percentage rather than by co-pay. I have had two very expensive treatments for my Polycythemia Vera at Mayo. Medicare pays most of it, more than if I had to pay a drug co-pay. What I get is an IV "shot" which takes about ten minutes, but the drug itself is expensive. It is to reduce my number of platelets. My platelets and red cells seem to be holding steady right now....maybe I won't need to do this again. My cost is primarily air fare and motel for this, which I can take as a tax deduction...but it's still expensive to go for this treatment which is done at only a few places.