When we give a neb, we typically bill an E/M code (99212-99214) plus the 94640. I noticed that one of our payors is bundling the two codes together but really are only paying the neb. This payor said we should be using the a modifier. Should we use a 25 modifier on the E/M or just bill the 94640 by itself? Does anyone have this problem? We use samples of albuterol so we don't not bill for that.